Fallout was really good, and I like both action-based and turn-based rpg's. Probably the most fun system for me is Strategy Rpgs, a la Final Fantasy Tactics or the Shining Force games.
For a regular rpg I think a turn-based system that utilized movement rate, terrain, cover from terrain, and pretty much everything around (within reason) would be pretty pimp. I like thinking and taking my time rather than twitch gameplay. And if I could duck behind that barrel and pop up to take shots with my crossbow it would do a world of good for my immersion into the game.
I really like DD too though, so as long as it's a good action game I have no problems with that.
