Quoted By:
Gen 4 for me. It's what got me back into the series after not playing Gen 3, and I remember having a tone of fun with it. I didn't particularly like any of the Sinnoh starters when I first saw their Basic stages, so I only used my Piplup once to go out and catch the first pokemon I saw once I could catch one, and it was an adorable Shinx that I named Fiera. I then boxed the Piplup and use my new Shinx like a starter.
It was the first generation where I actually managed to catch them all, and I transferred all of the pokemon to Black, then Black 2. It really sucked when it got stolen.