It sounds like a serious power issue to me, too. A surge protector has what's called an MOV (metal oxide varistor, I think) that can take one hit and then you might as well throw it away. I'd recommend a real, honest-to-goodness Uninterruptible Power Supply of reasonable quality (under $100). I've been using them for years and wouldn't trust anything less.
You might invest in a new power supply for the computer and see if things improve. If it doesn't make any difference, at least you've got the start for your next computer.
The malware thing is intriguing, too. If you aren't well-enough protected, enough running processes in the background can overwhelm your memory and pagefile and there just isn't enough left to allow the computer to start. I've seen gigabytes of cookies filling a hard drive and preventing XP from starting, too. They were a result of constant pop-up ads that added cookies continuously.
Edited to add: Of course, since you've reloaded, it's unlikely that it's anything but power.
Edited by Herk, 04 April 2005 - 09:56 AM.