Some General Questions about Sys Performance

Hi,

I have a 200 mhz NEC with 48MB Ram.  However, I'm not entirely happy with how it's running.  I've run the Nuts&bolts defragmenter but without too much of an improvement.  I have a few questions and would appreciate some suggestions on optimizing the performance of the machine.  For the record, I have a bad habit of downloading quite a bit of software and installing and deinstalling (using Cleansweep or Windows Add/Remove) them.

1)  When I press Ctrl+Alt+Del I see a whole lot of applications that I don't believe I need -- for instance, there's a "microsoft payment reminder" process, an "Intellipoint Wheel" process etc.  How do I find out what is essential and what is not?  Having done that, how do I decide what to keep and what not to keep.  

2)  Using Nuts and Bolts, I can figure out which application consumes how much RAM and System Resources -- often they go hand in hand; however, sometimes some applications consume a lot of RAM but very little by way of system resources.  What determines system speed?  That is, should I economize on the use of RAM hungry applications or System_Resources hungry applications?

3)  I was using Magnaram which seemed to increase the RAM by quite a bit. Also, it was improving the swap perfromance (or so it claimed). However, I didn't notice any significant changes. A computer consultant I know told me that it was not a good idea using Magnaram since Windows does a pretty good job. Any thoughts?

4)  Any other suggestions on improving system performance would be greatly appreciated.  Also, any sources of useful information that you'd like to suggest?

Thanks,

anony