Computer reboots in Registry Cleaner
Constant reboots suggest a driver or hardware problem.
My guess is that you are using Windows XP, right? If so, go to Control Panel > System > Advanced > Startup and Recovery. Is "Automatically restart" enabled under System failure? If it is, uncheck it.
The next time the computer crashes it doesn't automatically reboot but shows you the error message in a blue screen. Write the error message (such as "IRQ_LESS_OR_EQUAL") down, it can help you to find the reason for the problem.
Did you do any changes to the computer before the problems started? Such as installed new ram? Or updated any drivers, such as video card drivers?
Here's a few websites about the subject that I found:
Hope this helps.
Anti-Virus
Corrupt Hard Drive (ran scandisk)
Corrupt RAM (ran this
Corrupt device drivers (crash has nothing to do with plugging stuff in)
BIOS caching (though I didn't test using only external caching, that was terribly slow!)
I tried a "Soak Test" from the first link and got nothing. Also, I looked in Event Viewer and the only thing it listed was a memory dump.
another registry cleaner / fixer