Thanks for the quick response. Is your advice based on something specific from the crash dumps, or just general advice for errors of this type? I only ask because none of the devices listed are actually being used (with the exception of SMI, which I'm unfamiliar with... System Management Interrupt, maybe?)
Unfortunately, the lenovo support website for thinkpads seems to have disappeared. Never a cop around when you need one, I guess. System Update still seems to work, but shows no updates available for those items. Will have to wait for website to return.
Some additional info I should have given originally: this machine has been running XP 32-bit with no bsods for about 18 months. sfc shows no problems, windows memory checker shows no problems.
I'm unable to force a bsod - it just seems to happen randomly.