While fixing the problem would be best, it sounds like you should be able to reduce the crashes just by avoiding George as a trader (go see him after curing Mardaneus, though). The dwarf Otho can repair equipment if you'd rather not invest a skill point in Repair yourself, and you'll probably find better equipment that George has to offer.
To disable or lower your hardware sound acceleration (though I'm not sure if that will help for non-sound related issues), click Start | Run, type in dxdiag and hit Enter, then switch to the sound tab.
Are you shutting down all non-essential programs (especially anti-virus) before starting the game?
Troubleshooting Tips (& manual install procedure) 
