After playing "Half Life" or "Star Trek Elite Force" I sometimes get the following blue screen when I attempt to shut my computer down. "A fatal Exception has occured at 0028:BFF88112. Press any key to terminate the programme etc. Pressing a key does nothing and the only alternative is to switch it off.The system re-starts as normal, but if I run scandisk it informs me that there are errors in the boot sequence or something similar. System :- Windows 98SE, Pentium 2, ATI Radeon, Norton System Works + Firewall etc., Sidewinder Pro. Any ideas would be appreciated. Thanks.