Second for guild wars 2, the world is huge when you first start playing, and though the initial levelling experience can feel like it takes a while, once you have hit the cap you can go pretty much anywhere. The story is pretty linear, though, so if you want a deep and complex story it might be better to look for a single player game.

I'd also say the combat system in Guild wars is fantastic, it's simple enough to pick up and not have to stress about playing the game, but if you want to engage and get better there is so much to learn about and improve.