Difficult to say without a bit more information. Have you edited any databases or installed any new updates lately? If so, the problem might lie there. You can also try deleting the currentdb and workingdb folders (the game should refresh them) in case there's a corruption in one of the files in those folders. That often leads to random crashes.
Your videocard is not supported by the game?
Same problems other users encountered when installing/playing Live 2000 with Windows XP or the game might not be compatible with Vista?