Not sure if it's strictly DOS, since it's Windows 95... but that uses DOS... anyway!
I've got Fallout working under Windows XP SP with the compatability mode option, this installed the game and I've been playing it. There are two problems now, which have become rather annoying.
1) The screen often goes completely black, moving the mouse reveals a small scqaure section each time and loading the character sheet gets everything back to normal. But it is still annoying.
2) The game occasionally crashes. I've only noticed it in the south raiders camp. But considering I'm in a spot of difficulty in the raiders camp (heavily outnumbered and fighting my way out from the middle) I find myself have to reload rather often. Seeing as it crashes all the bloody time in this section, I'm sure that you can see how this might be infuriating. Worse still, the save games seem to currupt and become unable to load if I try to save anymore in the raiders camp.
So, I don't suppose anyone has any possible solutions. I'm running it undser the 1.1 patch. And I'm using the latest ATI catalyst drivers with a raden 9800 pro (if there are any compatibility issues there).... I don't think there is anything else out of the ordinary... it's on a SATA Hard drive, can't see who that would make a difference though.