More info: Blocking all services & start-up programs from Creative didn't solve the problem - I still went BSOD wiithin 10 minutes. However, if I use msconfig to turn off all non-MS services & eliminate all start-ups, the system seems stable (it went overnight without a BSOD.) It appears my solution will be to turn on one service, let the system go for some period of time, then turn on another, etc. If nothing turns up in the services, I'll repeat the process with start-up programs until I locate the problem.
Needless to say, this is going to take a lot of time, but at least there's the hope of a light at the end of the tunnel that's not an oncoming train!