I tried to use the Windows XP CD to fix the problem now the computer gets stuck on "restarting setup".
Oops. What you should have done was to start in Safe Mode and try to reload the driver. Running Setup would mean you have to go through the long process of reinstalling Windows and re-downloading all the updates.
From Safe Mode, you could have set the standard VGA mode - 640x480 16 colors, then restarted in normal mode and tried to get the driver back in. I'm guessing that the card would have supported that configuration.
An alternate way to do it is to install a PCI video card, then reload the drivers from the CD that came with the Rage Pro. I usually keep one or two of 'em around for just that. (And to test for a bad card.)
I guess it's fair to ask: why did you disable the card?