Let's sort out other standard problems:
- Update your graphics drivers. (which one do you use btw?)
- Deactivate anti-virus/security software (go off-line before, if you feel unsafe)
- Don't install the game into Program Files but into a custom folder like C:\gog.com\

Even when you're using an Administrator account, try right-clicking lithtech.exe => Run as ...

Try setting compatibility mode for Windows XP (right-click lithtech.exe => Properties => Compatibility tab); Then start the game with lithtech.exe;