So here's my deal.
Somehow I got two Windows Xp on my computer. I don't know how but I am able to choose which one to go to when the cpu starts up. The top one I usually use for the internet and misc. while I use the bottom one for video editting. It has worked for me just fine for almost 2 years. I have had minimal problems.
But, just the other day I was restarting my computer the appropriate way to log onto my other windows. The next thing I know my monitor doesn't even read the fact that it should be turned on. The monitor acted like it was in sleep mode. I fiddled with the wires and restarted both the monitor and cpu a few times. The monitor would said there was nothing plugged in for a breif second and then go back to sleep mode. I finally decided to give it a while and turned it all off.
I came back a day later and turned it on and everything was working fine. I decided to resart and get on my other windows and the same damn thing happened. I turned it off and came back an hour later and got on the Windows I wanted to get on and it acted just fine. It wasn't but about 10 minutes into and the cpu completely froze up. I restarted and went back to that same windows and it took about 20 minutes before it froze again. I restarted yet another time and then the monitor did the thing again where it slept.
So today I brought a different monitor in to make sure it wasn't the monitor. Thankfully, it's not beacuse it did the same thing. Now within the past hour or two I'd try to access either of my Windows and both would load and freeze up in loading position. One time I got to one of the windows and I was at the desk for about a minute with no mouse or keyboard response and figured it froze again. But now I can't get in anywhere. I tryed going to safe mode and it gave me a list of drivers and stopped at "system32\drivers\alim1541.sys". I have desperately searched for this on the internet with minimal results. So I know this is long, but it's vital I get some help. I am praying there is no reformating involved cause I got video on tehre that can't be replaced... I initially thought it was video card but now I kinda think it's my motherboard. What do ya'll think?
Oh yeah, I built the cpu myself. 80gb. 2.1ghz. 2.1Gb memory. I don't remember much else... but like I said, it's really my first problem so the otehr stuff is pretty good.

Thank you!

Before you go any further, I'd suggest throwing your hard drive in a friends computer and backing up your stuff. I'm thinking it could be a heat problem, at least to start. When it goes into sleep mode, do the fans still run? Do you have a PC speaker in your case, does it make any noise? Try and download the drivers you are missing and drop them in when you hook it up to a friends computer. This is just a shot in the dark however, it could be a hardware issue...

i agree with the other guy it is most likely an heating problem check if the cooling is right, i mean ur fan and stuff is working properly try running ur pc with ur cabinet open(last resort)
have u instaled ur xp in the same partion or diff one??? u have not explained this???

this could also be a problem.