generation 1 is my favorite because I was huge into Pokemon back in the 90's...
also played generation 2, and really loved it, but after that I quit playing Pokemon because I thought I outgrew it...

now years later, I decide to buy my son a Nintendo 3DS and PokemonX... and I gotta tell you I'm having alot of fun playing it... its been so long since I played pokemon but I think they made alot of improvements since I was younger