What's your favorite Pokemon generation? This poll includes only the main entries in the series and not the spin-offs. (No Mystery Dungeon, Pokemon Ranger, etc.)
Personally, I find Silver/Gold/Crystal to be my favorite. They're all undoubtedly great, but which do you find to be the best one?

My personal favourite has to be the fourth gen (AKA Diamond/Pearl/Platinum)

This generation included a lot of my favourite mechanics, such as the move split, as well as a decent story and appealing region.
This was by far the generation that I went back to the most, since there was just so much more to offer in terms of gameplay, and variety of pokemon that actually felt different and attuned to my style. 

Local Nods: I think this should be in the pokemon forum

My favorte pokemon generation is gold, silver, and crystal. It has a good storyline, and your rival changes character a lot over time. I also just adored the NPCs and towns. Plus, while usually there's not much else to do after beating the elite 4, in this game it's much different-You can go to kanto and earn 8 other badges! I love that. When I was 6 i completed the whole game, and beat Red in Mt. Silver. I loved the second generation of pokemon.

My favourite Pokémon game would have to be the ruby sapphire and emerald but all of the Pokémon games were all good so I have no complaints loll :-)

My favorite generation of Pokemon was definitely the Hoenn games. Though I admit there might be bias. Emerald was the first Pokemon game I spent hours on. I played Red sure, but I never really paid much attention to it. I beat the game and that was it. I skipped the Johto games, which I kinda regret. But then I got Emerald, which I adored. Beat the game many times, and spent a long time trying to beat the Battle Frontier. So suppose Hoenn is my favorite region. Mostly just because of Emerald though.

Popeye116 : Amen to this post. It really was cool to go through a whole new area with 8 more badges to get. And the NPCs and events were changed a bit so you weren't playing through Blue/Red again.

It has to be Generation Two. My first games were Heart Gold and Soul Silver, and I love them! You get to explore two regions, which means sixteen gym leaders and two Champions. Plus, your rival is a criminal! At least in the beginning.

Generation two is my favorite. I love tyranitar the most. Every time I can I get a tyranitar and name it Crystal. It also has to be female in honor of my first lavatar.

There is no doubt that the second generation of pokemon is the best. Even where you find the pokemon, in Johto, is the best in the series. There are many pokemon that were added to the national pokedex and there were very few that I did not like. I think I will say that Aipom is my favourite from the generation mainly because Aipoms just look awesome! Yes the stats are pretty bad but hey, Aipoms have hands on their tails and there is not anything better than that. 
I becomes obvious that Game Freak liked their own idea with all the hand stuff, so they reused it on a different pokemon. I do not know much about X and Y and 6th gen pokemon but I do know that there is a rabbit with hands on its ears, essentially copying Aipom!!
It is a shame pokemon became quite generic and boring since 4th gen came out. 3rd was ok but 4th ruined it all...

Generation Two! I played Heat Gold and Soul Silver, and I find them simply amazing! It was, without question the most impressive. generation out of all six of them so far. Even if it is shortest.