VV5 is 1024x768, instead of the 800x600 size we used for previous games. That size has many benefits, but it can present problems on computers that don't support resolutions higher than 1024x768. Without knowing the specific error code you're getting, I can't say exactly what the problem is, but (assuming that it's due to the display size and resolution) the procedures in this post should help you. I have tested VV5 in full-screen mode on older computers that supported only 800x600, and it worked fine.