This is a very difficult question; there are a lot more than 6 Pokémon I like, and when it comes to deciding teams, I really like to take types into account.
I guess my team of choice would be:
Jolteon
Daikenki(sub: Vaproeon)
Torterra
Charizard (Sub: Fearow)
Lucario (Sub: Nidoking)
Aggron (sub: Umbreon)
Jolteon and Torterra are the only consistant choices on my team, however. I will change out with other Pokemon if I want.
Edit: And here, months later, my Dream team is vastly different.
Jolteon, Fearow, Vaporeon, Beedrill, Vileplume, and Espeon are my current favorites(October 12th, 2011)