I have a Compaq Presario 3100, XP. It is very sick... to me anyway. I can not run a scan without it crashing and it tells me to contact the System Administrator. The last blue screen said something about BIOS updates and disable caching/shadowing. I can not run registry fixes, spybot -search and destroy, windows defender etc without it crashing. I can run my AVG tests. When I start it up I get the rectangular boxes and know that I have two items in the start up that show the rectangular boxes and HKCU\SOFTWARE\Microsoft|Windows NT\Current... I also have lots of cd drives listed - which I do not have. I try to remove them through the device manager in safemode - but they always return.

Please - what can I do? Thank you.

Sounds like you've got some malware on your PC.
I would recommend The Ultimate Boot CD
You might also want to try Hijack This. Be careful with HijackThis though, you can do more damage than good if you don't know what you're removing.

What is the exact crash error?
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