If you were a Ranger and could choose any partner, what would it be and why? Do you just really like the Pokémon, or do you think it would be useful, fits your personality, etc? I guess you can include Gen V in this, but kindly don't assume your partner Pokémon would be a legendary/psuedo-legendary/ridiculously overpowered Pokémon. (Just imagine a Ranger barreling through a forest with a Salamence or Metagross or something blasting trees out of the way. Kind of counterproductive, yeah?)
Anyway, I think I'd love to have a Bellossom, Snover, or a Ponyta. Bellossom because it just seems like it would fit a person protecting the environment (and I really love Bellossom!), Snover because its ice/grass attacks would be really handy in a pinch, and Ponyta because I also really like Ponyta and it would be a good way to get from point A to point B quickly.
If I were to include Gen V, I'd also look at Braviary. Many Rangers in the games use flying-types as their partners, so they're quite useful, and I think Braviary is so cool. :3
/lame attempt at undeadening the OPG section