Probably Dragonite, or as daft as it sounds, Growlithe. I'd either want a really bad-ass Pokémon that could fly me anywhere, and make me feared, or a Pokémon I could snuggle up to and keep warm and make my dog jealous. >D.
Failing them, something like a Celebi? Go forward in time, see football results, return and bet on them?
I'm sure the above has been an influence in a film resolving around time...~