Definitely Gen 2. That was the only gen I didn't have a starter I truly loved. I made do with a Chikorita though. (back then I wouldn't throw away a starter) There wasn't even a starter in gen 2 that I disliked, they just seem drab compared to the other starter sets.
Each gen usually has a starter I love, one I don't like and one I'm initially neutral on but grow to like it in time.