I have a lot of similar answers to 'IcyKerpymon'.

A Pokemon - Milotic, because they are beautiful and I love them :P
Gym Leader - I would run an Ice Gym, preferably the 7th one. I'd have Milotic, Glaceon, Togekiss, Piplup (unevolved), Lapras and Dragonair.
A Ranger - Glaceon, Piplup, Milotic or Delcatty
A Trainer - I'd be a coordinator and trainer. I'd have Milotic, Glaceon, Togekiss, Delcatty, Blissey and Piplup.
If you had any Pokemon Ability - Pressure would be cool!
If your pet was a Pokemon, what would it be? - Probably a Delcatty and Glaceon