When I turn on the computer it starts to go through it's startup and when it GETS to windows starting up it restarts the whole computer and does the same thing over and over (occationally SHOW a screen to us the last known working startup) which does nothing. I think it's a hard drive problem (5 YEARS old). My old computer is doing the exact same thing. It is also about that old or older. It will start to boot up and the log on screen comes on for about TWO or three seconds and then it starts to reboot over and over again. I tried to load windows xp again but it won't load.Welcome to CH!

Have you added a hardware or installed softwares prior to this?
Or you can boot to safe mode and check Device Manager to see if there's a conflict with your systems.Can you boot to Safe Mode?Bawlsac please post as much info on the MACHINE as you can...

warnlori it's best to start your own Topic so it can recieve the proper attention and also include a lot more info as well.Have the drives been scanned for viruses? Did you try using the XP disc to try an repair the OS