I have a similar problem.
I need the video card to do 2D because with any other card, the TV adapter that I have won't work.
Some games (like ms flight sim) require both 2d and 3d to play. The voodoo card that I have only does 3d so that mostly works, but its not a perfect solution. Is it possible to tell some games to just other another card and not have that interfere with anything else?