I'm sort of torn on this; one on hand, I feel like Fallout 3 / NV would fit perfectly from the game side of things, but Fallout 2 (which wouldn't), has the best style of writing (in my mind, I'm biased as hell) to suit a mind series.
Although granted, especially with NV, mods get you a long way, so I suppose that is the best way to go about it, if you have to go with any fallout game.