Hello,
Start>Right click on Computer>Properties>left side Advanced Settings. In there under teh Advanced Tab under the startup and Recovery turn off the Auto reboot on system failure. This will STOP the PC from rebooting right away on a BSOD. That is Vista. XP is almost hte same except you dont have to click the Left side advanced.
Do that and see if you can get the BSOD up again. Until then there is nothing we can do to help.
Cheers,
Mak