Just so people here can get a better grip on your problem, how did you carry out a System Restore?
You said that when you rebooted, the computer got stuck on the blue progress bar, then reboots to the first boot screen again.
As you can only access System Restore once you have loaded Windows, how did you do the System Restore?
I installed Windows XP Home Edition with SP1 on a brand new home built computer and downloaded the beginning programs, firefox, spyware blaster, I visited microsoft.com to install all the updates ; SP2 I believe among other things, and when I shut the computer down to finalize the installation of the updates it did not boot back up. It just stays on the Windows XP screen with the moving blue bars then goes black and goes to the first boot screen again. I system restored to before the updates and tried to install them before I installed all my other programs and when I restarted it after the installation it failed to boot up again? Any ideas as to what's happening will be greatly appreciated. Thanks