no win xp, just black screen and hourglass

I am having serious problems with my pc. I don't even know if this should be a hardware or software question. A few days ago my pc started acting up on me..shutting down and so on, and through reading old threads I was able to determine that my power supply was going, then it completly stopped turning on at all so I took one out of another pc (same specs) and swapped them out, and Everything resumed working normally. Now today I turned on my pc and it was acting incredibly sluggish, so I opened up task manager and it said that my windows messenger (cant remeber exact way it was written but thats what I got out of it, was written in caps and said .exe at the end) was running at 99%, and my total cpu usage was 100%. I couldnt do anything so I just let it sit for awhile, when I came back the windows messenger icon at the bottom in the toolbar had multiplied itself....there were like 14 of them across the bottom. I rebooted the machine and the same thing happened again. A friend recommended that I just use my windows restore disk that came with the pc and start fresh, so I did after backing up any files I wanted to have. The first time I ran it it said that it couldn't open a few .ghost files then said there was an invalid dump file and popped the cd back out, and when it rebooted it started out with the windows loading screen, then went to a light blue screen like the sign on screen, but it only said windows xp and emachines across the top. I powered down the machine and turned it back on later, now I get the windows loading screen and then a black screen with an hourglass on it, I tried booting into safe mode with f8, but it said setup wasnt complete and to run setup again, so I did. This time it finished all the way through both discs, but still stalls at the black screen with an hourglass when I reboot, it has been that way now for 2 hours. Any help would be greatly appreciated..and I am sorry for the length of my post, I just dont want to leave anything out that might be relevant. Thanks in advance!

 

I would recommend that you try replacing your CMOS battery. Its easy and cheap to do, and can cause all sorts of whacky problems. For the effort it takes to replace, its worth eliminating as a suspect.

 

I tried safe mode again, this time it said it couldnt load windows because it is missing a file or it is corrupt: \windows\system32\config\system. I am going to look into the battery, but I live in a very remote area and I will be driving an hour to get there, so I was hoping I could fix it in the meantime, still intend to change the battery regardless so I dont have problems down the road. Thank you

 

I also forgot to mention in my previous post that it says I can try to repair the problem by using the restore cd and to push r at the first menu, but I only have a emachines cd, it doesnthave any such menu, just restore or boot from disc. Is there a way that I can manually repair it? I'm starting to think it may have been a virus and I should have went that route rather than taking my friends advice, now its so screwed up I cant run anything. I did have trouble getting my firewall to stay on and couldnt run my antivirus right before this happened-can a virus do this?