Clicking Start causes explorer to crash

Have you scanned for viruses?

(List credit goes to CrazyOne)
Online Scanners

Norton Web Services  
Go to this page and click on Scan for Viruses
http://security.symantec.com/ssc/vc_about.asp?j=1&langid=us&venid=sym&plfid=22&pkj=REODSKVYRMHCGVRVRMN

It needs to download a few file so as to activate the scan so you may see a message like this.

"The Scan for Viruses uses an ActiveX program to scan your computer. The download is approximately 1.5MB and can take about 10 minutes over a 28.8 modem.

The scan can take more than 20 minutes depending on the speed of your computer and the number of files that you have. Please do not browse away from this page unless you intend to abort the scan.
 
Downloading Scan for Viruses controls. Please wait...
 
During the download, you might see one or more messages asking if it is OK to download and run these programs. Click Yes when these messages appear.

Note: Scan for Viruses does not scan compressed files"
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Trend Micro HouseCall      
www.housecall.antivirus.com
"Trend Micro's free online virus scanner
In order to better serve our customers, we ask HouseCall users to register before scanning their computer.  By registering, you will receive virus alerts from our team of Virus Doctors. You will be able to unsubscribe when you receive your first email. You can also scan without registering"
http://housecall.antivirus.com/housecall/start_corp.asp
======================

PC Pitstop Virus Scan
Our free Web-based virus scan uses Panda Software's award-winning technology and virus list. We're checking against the "wildlist," the roughly 200 viruses that are most prevalent in the world in a given month
http://www.pcpitstop.com/antivirus/default.asp 

Adware?

Check for adware and spyware

spybot here
http://spybot.safer-networking.de/
Download
http://spybot.safer-networking.de/index.php?lang=en&page=download

AdAware
http://www.lavasoftusa.com/

Spycop:
http://www.spycop.com/

BHODemon and Hijack This and Browser Hijack Blaster
http://www.spywareinfo.com/downloads.php?cat=sp#det
BHODemon | Think of BHODemon as a guardian for your Internet browser: it protects you from unknown Browser Helper Objects (BHOs), by letting you enable/disable them individually. This program is my choice for BHO detection and is highly recommended.

Browser Hijack Blaster | Running silently in the background, Browser Hijack Blaster only springs into action when an attempt is made. It watches and protects the following items: IE Homepage, IE Default Page, IE Search Page, BHOs. Whenver one of the above items is changed, or a BHO is added, you are immediately provided with information on the item, along with the option to keep the change, or revert to your previous settings.

Hijack This | Written by a member of our support forums and based on our Hijacked! article, this program scans the locations in your computer system that may be modified by browser hijackers and fixes any problems found. An easy-to-understand tutorial is available at TomCoyote.org.

General and overall information about Spy/Adware
http://www.cexx.org/adware.htm 

:o)

Bartender_1

Once you've verified you're free from those:

Check http://windowsupdate.microsoft.com
download and install the latest patches and service packs for your Operating system.
If you already have the latest service pack, try re-installing it.

Hope this helps!

:o)

Bartender_1

It sounds like there is no error message given.

Try running chkdsk (or check for errors on the drive if you can get to the GUI)

thanks guys

well its not a virus and stef you are correct, there are no error messages with this.  Nothing appears in the event viewer either at the time of the crash.