Full Screen DOS in Vista

I use an old DOS program that must run in full screen mode (it seems 
not to run in a window.) Using XP, it runs fine in full screen mode 
using an ATI video board. In Vista (32 bit), it will not run, and 
generates a message that it will not run in full screen mode (My 
Vista machine uses an NVIDIA video board.) I'm not sure if its Vista 
or the NVIDIA board that is the problem. Any thoughts will be 
appreciated. I need to run this program even if there is a way to 
force it to run in a Vista window.
--