Well, after playing with spybot and shutting down several services (and several versions of the video drivers), I've gotten so the slow down appears more randomly.. and less often. It's still 10-30 seconds, but I usually have enough time to kill one or even two of the Mutants before it takes effect. I can usually manage to win at least one battle before it crashes. I'll push forward, see if it improves when I reach an area with fewer Mutants.

At least that implies it *is* a conflict between drivers and system somewhere. No luck narrowing it down further, however.

Dervish