I always went with Squirtle in generation 1.
Blastoise was one of my favorite 1st gen Pokemon back in the day and was the easiest to start out with as a water type.
I hated Pokemon Yellow at the beginning having Pikachu to start with, when the first gym was freaking Brock with all rock type. That part of the game was a pain, despite Pokemon Yellow was more awesome than Red and Blue.