FFVII Bombing Mission for an RPG opening, definitely. I tend to find openings that explain the story to you a bit boring. I don't want to have to listen to or read a large narative explaining the history of the world, describing the characters, or what have you. That sort of thing can easilly be drawn out as the game progresses. I also hate games that force you through a tutorial at the start (Like FFXII). I get that it is supposed to make the player familiar with any new features and controls and all, but things like that should be kept as an optional feature. With a game, all I want to do is get in the action.
For games in general, I think one of my favourite openings is the opening for Batman Arkham Asylum. It was amazingly well-written, and I loved the tension it built up to the moment Joker breaks free. And when they introduced Killer Croc during that scene, I swear it made my hair stand on end.