I'd probably be just like Ash, travelling the world, catching Pokémon, and becoming a celebrity. That would be perfect.
As for two Pokémon that I'd choose?...
1) Scrafty - he just seems like a cool dude, ya know. I feel like I would get along with him really well.. :P
2) Politoed or Ludicolo - I dunno, comic reliefs?! They're always so optimistic and giddy, I could never be sad around them.
I base these choices on who would be my best companions... Like I couldn't have a Pokémon with a conflicting personality or bad feature. It's just like friends or band members if you're travelling everywhere with them.
I can choose tough guys, but... where's the fun in that?