Try unchecking the "backbuffer in system memory" box in the display setup (in-game).
If it's already unchecked, try checking it.
There is an advanced display properties tab, but I forget how to get it with the command line with the EXE.
However there is an option to run it automatically using Patch Commander (a free third party program). In the advanced display properties there are some options you can try messing with (although it only advises you to do this in consultation with LucasArts technical support).
Good luck! I don't have XP, but trust me, the entire DF/JK series should run under XP, just like it does under 2000!