Well charmander has high Special Attack low defense
Squirtle - High Defense/Special Defense low speed
Bulbasaur - High Special Attack/ Special Defense low speed.
So if you're looking for speed - Charmander's your best bet
If you want good defense - Charmander's not your best bet
If you want high defense - Try Squirtle
High specials overall - Bulbasaur.
I would choose squirtle because I believe that a good defense would get you farther than specials or speed. Yet bulbasaur would be my 2nd choice. Hope I could help