Silver FTW.
2nd gen rocks, it was so magical to discover that whole new region after playing RBY, each new Pokémon, each new town, each new character was an epic moment for me. These versions are so many memories for me. And I chose Silver especially because it is the game where I spent the most of time among all my Pokémon games, and even among all my games that aren't Pokémon. And I love this version.