>>12214763Gen 1-3, especially 2 ruled because of the sense of adventure. Hell, in Gen 2 you could get 16 badges and face Red. You don't get more awesome than that, it's the gen I have the dearest memories of.
However, Gen 3 introduced abilities. Abilities added a lot more depth into the game, now you could battle with awesome pokemon made really different from each other because of their unique abilities. I just felt shortchanged when I first captured a Run Away Poochyena and REALLY satisfied with my Route 1 Pickup Zigzagoon (best first route pokemon ever).
Gen 4 is really slow, B/W is good but you feel like the game's holding your hand through the whole experience and B2/W2 did nothing to alleviate that feeling. In fact, I think that B2/W2 is the worst excuse for a pokemon game ever.