Easy and free software to do it, just scan your registry: http://www.worldstart.com/weekly-download/archives/reg-cleaner4.3.htm

Many people also use CCleaner http://www.filehippo.com/download_ccleaner/download/cce8fe21916a4d3c9d82be054cf5519a/

You have options there to scan and fix registry related issues

Also, here's a good guide for optimizing XP:
http://home.comcast.net/~SupportCD/OptimizeXP.html

Is there a another way to clean the Regisrty besides using apps for it? Something more direct?

I checked the link OptimizeXP, but there no talk about the registry,

You can do it manually but you need to know a lot about registry structures. There are some books about it. It is very time consuming and even pros are using registry scanners. Books include: Microsoft Windows Registry Guide; Microsoft Windows XP Registry Guide; Mastering Windows XP Registry etc.

There are lots of utils that claim to 'clean' it, but the best method is to extract your keys using magical jellybean, backup all your data (dump your cache and history for all users then backup the Documents and Settings folder recursively, excluding the NTUser.dat files), format C: and reinstall windows.  Annually. Unless you have not installed and uninstalled, nor upgraded, any programs during the prior year, you *will* notice the difference.

Well, you can try Auslogics Registry Defrag (http://www.auslogics.com/registry-defrag) although some people say it really works and some people say it does absolutely nothing. And what do you mean by optimizing your registry? Do you mean tweaks? You can check:
http://www.pctools.com/guides/registry/
http://www.theeldergeek.com/registry_edits.htm
for that.

By optimizing I mean to make accesing the Registry faster & cleanning out keys not in use anymore.

Sometime back I found something similar to what Darr247 stated, but I can't seem to located.  It was a series of steps where u clean your registry by extracting keys, etc., but there was no re-instal of windows.

Very appreciative on the info u just sent.

Also I'm interested on how u use Virtual PC for to "avoid the clutter", if u can provide more info, greatly appreciated.

So in essence, there is no really Registry Optimization process or program out there that does what I'm asking in this EE question? Its really more a, part program and part one-self, on keeping eye on the registry and programs installing.

In your solution you offered to provide more explanation on the use of Virtual machine to avoid the clutter that accumulates with normal use; can you send me more explanation?

Thank you Ramante

With any of the "Virtual" PC programs I mentioned, what happens is that the software you install allows your exsting operating system to become a Host to another Guest operating system and run it in a special environment that does not mess up your existing Host operating system if things go wrong with the Guest one.

It's different from Dual Booting a computer, where two or more operating systems are separately and fully installed to physically separate hard drives, and a Boot Menu allows you to choose which one to boot to for that session.

If you have ever played a computer game that always needs to have the original setup CD in the drive while you are playing it, then you may have wondered if it was possible to somehow copy the CD to the hard drive and make the game look there instead of to the CD.  There are programs that allow you to do this, and what they do is allow you to make the folder in which the CD contents are copied into a "Virtual" CD that PRETENDS to be a CD in the CD-Rom Drive.

A Virtual operating system is similar in a way, because the software you install makes it so that the installed Guest operating system is running in a space that is pretending to be a proper hard drive space.  What you get is a Window within your existing Desktop area in which the Guest operating system is running on top of the existing Host operating system.  You can switch between the operating systems any time you want to.

It is important to note that the new Guest operating system must be capable of being installed on that computer normally if you were ever to do that.  In other words, you can't install some version of Windows on that computer if the computer doesn't support it, or if that operating system doesn't support your computer.  Remember, although the Guest OS is running in its own SOFTWARE environment, it is using the existing hardware of the computer just as the Host OS is using it.  You therefore need a computer that has enough memory, hard drive space, graphics power, etc to handle the Host OS AND the Guest OS.  So, if the Host OS requires a minimum of 512MB of memory and the Guest requires a minimum of 256MB of memory, then your computer should have no less than 768MB of memory.  I actual fact, you normally need more memory than the minimum specifications for any operating system to run well, so in the above example you would probably need 1GB of memory for it all to work well.

In addition to this, when you install your Guest OS in its Virtual space, you also need to be able to install drivers for all the hardware for whatever OS you are installing.  The Guest OS is a complete operating system, but is just running in a space that keeps it completely separate from the Host OS that allows it to run in that space.

Many system developers, programmers, testers, IT support technicians, etc have several different operating systems installed as Virtual ones using VirtualPC, VMWare or other virtual OS software.  This is not only so that they can test things on other operating systems, but also to give them the option of completely removing a Guest OS any time they want without affecting the existing Host OS.

So, say you have a Windows XP system and want to be able to run and test things on Windows 98SE.  Rather than having 2 separate computers running the different OS's, you could install Windows 98SE as a Virtual operating system on the same computer as you are already using to run Windows XP using your Virtual software.

You need to read up a bit on the different programs available to see whether this is something that suits your needs or is usable:

Overview of Virual Operating Systems:
http://en.wikipedia.org/wiki/Virtual_machine

Microsoft Virtual PC 2007:
http://www.microsoft.com/windows/products/winfamily/virtualpc/default.mspx

Brief overview of Microsoft VirtualPC:
http://computersoftware.suite101.com/article.cfm/introduction_to_virtual_pc
(Look also at "Related Articles" links at the left of the page, eg: VMWare:
http://www.suite101.com/article.cfm/linux_for_business/22326)

Older Virtual PC 2004 SP1 (not Vista compatible?):
http://www.microsoft.com/downloads/details.aspx?FamilyId=6D58729D-DFA8-40BF-AFAF-20BCB7F01CD1&displaylang=en
(Unofficial list of which OS's work and which don't in Virtual PC 2004:
http://vpc.visualwin.com/)

Microsoft Windows SteadyState:
http://www.microsoft.com/windows/products/winfamily/sharedaccess/default.mspx

Sun VirtalBox (Note - Innotek was bought by Sun):
http://www.sun.com/software/products/virtualbox/index.jsp

All free down to here, retail applications below:

VMWare Workstation:
http://www.vmware.com/technology/virtual-machine.html
http://www.vmware.com/products/ws/

Faronics Deep Freeze:
http://www.faronics.com/html/deepfreeze.asp

You will note that Windows SteadyState (for XP) and Faronics Deep Freeze are NOT applications to run Virtual Operating Systems.  They are designed to allow an administrator (or you) to completely protect the the Windows Installation from permanent changes.  They restore the original state from that set at any time by the admininstrator (or you).

Your other option in keeping with the "restore" concept is any of the well reviewed hard drive "imaging" applications.

PowerQuest Drive Image 7 was the last version of Drive Image by them before Symantec took them over and created Norton/Symantec Ghost:
http://www.symantec.com/norton/ghost
http://en.wikipedia.org/wiki/Ghost_(software)

I prefer Acronis TrueImage to Norton Ghost simply because I don't like Symantec products in general:
http://www.acronis.com/homecomputing/products/trueimage/
http://en.wikipedia.org/wiki/Acronis_True_Image

TeraByte also offers good products that apparently perform well:
http://www.terabyteunlimited.com/image-for-windows.htm

Paragon Drive Backup:
http://www.drive-backup.com/

There are other very capable products, and each person has favourites, so perhaps searching google for "drive image software reviews" may find a comparison chart based on expert reviews.

Other Backup Utilities:

Drive Image XML by Runtime Software
Free for private use and allows creation of backup drive image in real time, but no user support:
http://www.runtime.org/driveimage-xml.htm
http://www.runtime.org/driveimage_faq.htm
Tutorial: http://www.youtube.com/watch?v=PTEnKA7tOXM

Shadow Copy by Runtime Software:
Allows you to backup individual files, folders, or all drive content to another drive, and is able to copy files that are currently in use:
http://www.runtime.org/shadow-copy.htm

Note: the 3rd-party version of Windows XCOPY.EXE named XXCOPY allows you to copy entire hard drive contents, including hidden and system files, but isn't as good as Shadow Copy:
http://www.xxcopy.com/index.htm

I hope this helps you.

>>> "So in essence, there is no really Registry Optimization process or program out there that does what I'm asking in this EE question? Its really more a, part program and part one-self, on keeping eye on the registry and programs installing." <<<

Yes, I would say that is correct.

About the best thing to do BEFORE you run any setup program is to export a "before.reg" file, then run the installer and export a "post_setup_pre-config.reg" file before actually running the program, then run and configre the program and export a "post_setup_post_config.reg" file.

Just download, unzip to its own folder, and run the free ExamDiff.exe program telling it to compare the first *.reg file to the next, and then that one with the last.  It will give you a good indication of what registry keys and values were added by the program so that you can go back to check that they were removed or reset when you later uninstall the software.

ExamDiff Free Version 1.7
Installer Package: http://www.prestosoft.com/download/ed17_setup.exe
Standalone Program: http://www.prestosoft.com/download/ed17.zip

ExamDiff Pro retail version (has some more features):
http://www.prestosoft.com/edp_examdiffpro.asp

I use the very much more featured retail program "Beyond Compare" for comparison functions:
http://www.scootersoftware.com/

If you really wanted to get very in-depth into post uninstall cleanups, then you could install a program that monitors everything the setup routine does, so that it can remove the left-vers later, eg:
http://www.innovative-sol.com/uninstaller/manual/installation_monitor.htm
OR
you could do the *.reg exports I mentioned above and also create file listings of your hard drive pre-setup, post-setup pre-config, and post-install post-config.
A free utility like this makes it easy to create listings:
http://www.karenware.com/powertools/ptdirprn.asp
and the ExamDiff program can compare them.

You also have the "DOS" commands you can use like this manually to create each listing, then in a batch file to compare them afterwards:

dir /a /on /b /s c: > c:\progname_pre-setup.txt
dir /a /on /b /s c: > c:\progname_post-setup_pre-config.txt
dir /a /on /b /s c: > c:\progname_post-setup_post-config.txt

@echo off
start C:\Program Files\ExamDiff.exe c:\progname_pre-setup.txt c:\progname_post-setup_pre-config.txt /i /w /b /l /e /t /d /n
exit

Thanx Lots BillDL...for both followups.  From what I read, I just come up with several great uses for the VPC environment.

Again Thanx!

You are welcome Ramante.

> About the best thing to do BEFORE you run any setup program is to export a
> "before.reg" file, then run the installer and export a "post_setup_pre-config.reg"
> file before actually running the program, then run and configre the program
> and export a "post_setup_post_config.reg" file.


Doing that for installation of every program sounds like a LOT more work than just reinstalling windows once a year. ;-p

Not really.  Of course, I do agree with you, but the "best method" statement was suggested as a method of trying to keep the registry clear of accumulating debris left from uninstalled software.  The suggestion was made in reply to the acknowledgement that there IS no real way to "optimize" the registry, that's all.

I agree that the best way of maintaining Windows is "just reinstalling windows once a year".  The best method for keeping a car's bodywork looking good is to polish it every 3 months, but it's also important to wash it once a week.  Some folks eventually get fed up washing the car knowing it's just going to get dirty during the next journey, but others are meticulous and keep washing it each week without fail.  User's choice in the end.  Depends how obsessive the person is really - no, I'm not going to use the word "anal" ;-)

It sounds like a lot of work, but just run commands to do it or use batch files.  Substitute "progname" to a short name reflecting program being installed.

Run batch file No. 1:

@echo off
regedit /e c:\progname_pre-setup.txt
exit

Run Setup to completion and reboot if prompted.
Run Batch File No. 2:

@echo off
regedit /e c:\progname_post-setup_pre-config.txt
exit

Open and configure program.
Run Batch File No. 3:

@echo off
regedit /e c:\progname_post-setup_post-config.txt
exit

Anyone running downloaded installation packages should keep them stored somewhere for future use, and that's the place to move the registry exports into.  Do a comparison and create a quick report using ExamDiff after UNinstallation of that software, and check Regedit to ensure the keys originally created by the software are deleted.  Doesn't take long.