Are you shutting down all non-essential programs (especially anti-virus) before starting the game?
Try running the game as administrator, and in the compatibility options disable desktop composition (in Vista/7).
A quick google search brought up an old topic for a different game and Vista SP1 where people recommended updating/re-installing sound and graphics drivers. One person reported getting the game to work by disabling visual themes in the compatibility options.
StackHash and Application Crashes on Windows - "Here’s how 99 percent of Vista users can fix a StackHash failure."
Stackhash APPCRASH problem:
techsupportforum /
tomshardware[PC] Support FAQ - The Dragon Knight SagaTry emailing support@larian.com, with a description of the problem and maybe a link to this topic (see the DKS
support page).