In terms of "open world" games, if you haven't put STALKER in your god damn computer you're fuckin' up. STALKER's gunplay isn't something that's easy to get used to, and you'll be doing a lot of walking, but there is a lot to do. That and modded Morrowind. I personally couldn't get into Morrowind too much, but the world, the characters in it, and the story around all of it is incredibly interesting to me and I'd probably end up giving it a chance again.
KalkinDungeons and Dragons or any other tabletop RPG with a good GM.
Real.
The stories I've heard about DnD are amazing. I've always wanted to try it but I live in the old people borough where usually enjoyable things enter a no fly zone.