First off, thank you so much for your reply. I'll read all of your suggestions and proceed as instructed. Thank you for your time.
SP1 is installed. Perhaps it installed after I posted the above information (???) I checked computer--> properties, and it's stated as already being installed. I've also uninstalled the two software you suggested. I doubt AVG is the culprit as I always used Microsoft Security Essentials over AVG during the BSOD anyway.
I'll try playing some games now

and see what happens, and report it right away. Once again, thank you for your time.