The first thing you need to do is stop the computer from rebooting so that you can find out where the problem is. Goto the System Properties (in XP right-click on My Computer and select Properties). Select the Advanced tab and under Startup and Recovery press the Settings button. In the Startup and Recovery windows uncheck the System Failure option Automatically restart. Press OK twice to exit. Now cause the problem again and the BSOD will stay on the screen so that you can read it.
The information you want is the error reason in the upper left of the screen and if there is a driver at the bottom of the screen that is causing it, copy down the driver name too. Then go to the manufacturer that makes the driver and try and get the latest version to update to or contact the manufacturer and send them the error message and see if they have a fix. Googling the error message should also uncover lots of useful information.
~jr
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