It would be awesome to live in the Roller Coaster Tycoon 2 world, provided that I could still design the parks from inside as well. I could walk around the park and ask guests what they thought of the park, not knowing of course that I built the whole thing; and I could visit the parks of others and admire their creations as well as my own. It all sounds silly, I know, but I think it would be a great world to live in.
On the other hand, if I lived in the Sims world, I'd never have to make decisions for myself...
I'd go nuts over even a day in the world of Resident Evil, Silent Hill, Dead Space, or Parasite Eve. Preferably Resident Evil I suppose; Silent Hill's creepy ambience fades on you, Dead Space's human population seems pretty, hmmm, expendable (I'd like to survive the whole day if I could, hahah!) and Parasite Eve, well, if you're not Aya, you're nobody.
If I was going to be a regular citizen then Mario, everything just seems so carefree in that world! If I got to be a character that I wanted to be in that specific world then Batman or Ezio or Niko Belic or Nathan Drake or any FF world cause being a regular citizen in Assassins creed for example would be the same as going back in time and living a normal life!
I would live in the world of Gladius, where I can kill people in the Arena and get paid for it! And I would be a Minotaur of course, which is another reason why I have this user name (there are Minotaurs in this game). But if I can't do that then I would be in the world of Tekken (5, 6, or TT2). Then I can fight some cool video game characters.
To the best of my knowledge there is no pc or consol Equestria video game, well, there's that one flash based game somewhere so I guess that counts? :3 Yeah I'd chose Equestria.
I'd have to say one of the Zelda games. You can get gems from bashing pots and mowing the lawn. Or the Cave Story world. Quote may never say anything, but I think he'd be cool to hang with. Also Curly Brace is hot.