Alright first things first, we need to identify the problem.
1) Installed any new hardware recently?
2) Installed any new software recently?
3) Did any other major changes like a system restore? Or a driver change?
If so, Try reverting/uninstalling using a process of elimination, if the crashes stop after removing something your all good to go
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Some ways of fixing the issue, Download and update all your drivers to the most current version, Download a program called CCleaner and use that to clean out all the junk and fix the registry.
CCleaner can be found here:
http://www.ccleaner.com/download/
Run a virus scanner like Trend Micro's online virus scanner, its always up to date. If you cant run it without the computer crashing get another computer connected to it, launch it on that machine and scan your machine.
Trend Micro's house call can be found here:
http://housecall.trendmicro.com/
Download and run Adaware SE to remove all that spyware junk it can be found here:
http://www.download.com/3000-2144-10045910.html
Next to try and find the source of the problem, You might have to improvise on some of the steps as I'm using Windows Vista at the moment, which some things are vastly different than XP.
Alright goto:
1) Start
2) Control Panel
3) Administrative Tools
4) Event Viewer
Now on the left of the event viewer should be something like "system" (Its a folder type icon).
Now there should be a huge list of crap errors and other garbage, what you want is to find the event that caused the crash, There should be some icons which display an error symbol of some sort basically this is where you have to improvise, I need to know the event that caused the crash, And then tell me the information thats inherited within that event. (Print screen will do the job).
Just double click on the event with the error and print screen it. If you have more than one error, well, right click on the system folder, and delete all the contents, wait for the next crash then do those steps again and print screen it, Hopefully there is only one error, Or just bring up all the errors at once or something. The errors with the yellow "!" symbol isn't anything serious, So don't bother about them.
Hopefully my other steps have helped ya out.
