Yellow because at the time I was playing it the TV show was on aswell (The older Pokemon TV Series), I used to love it as a kid but never seem to buy any of the new pokemon games...

gold/silver. The second gen pokemon kick every other pokemons assess. All new types were added and it just make the pokemon look baddass, like seeing a steelix for the first time xD

Yellow comes close, but pikachu sucks

*runs*

Pokémon Blue.

When only the first gen existed.

Gold...yellow was my first, but I used to stay up half the night just to play gold,

Pokemon Gold - My brother brought 2 gameboys and pokemon gold and silver and he gave Gold plus Gameboy to me for my birthday and i remeber we would play for hours and hours it was sooo cool and when my 2 cousins came over (my parents had to babysit them every saterday and sunday) they would bring there gameboy over and pokemon games and we would all play pokemon all day and trade and battle and stuff and we would allways fite too see who got to play on the TV screen (via pokemon stadium 2 N64) but since my brother was way older then us he allways got to (he allways bossed us around lol) its probly my favorite childhood memory playing pokemon with my brother and cousins

i must have been about 10

i think it would have to be red.  first one of something is always hard to top

i still remember what some areas looked like and what i would do there.  the first forest you get to and working on levelling up metapod and searching forever to find a pikachu.  later finding and loving ponya.  it was just the first and i loved it.  spent countelss hours.

now the best played since has to probably be white.  besides i liked how they made it 100% new pokemon until you beat the game they made the menu working so much easier to do stuff in it. 

leaf green. the first set of pokemons rules, then it died out......for me anyway.

Silver for the original GB, because all the pokemon after that sucked and looked lame (except for a few legendary ones)

It's hard, because the original Red/Blue will always mean so much to me as a gamer. Gold/Silver introduced Dark types (my favorite) and one heck of an adventure that spanned two lands. Black/White is a fantastic game in so many ways too, from the much more engaging adventure to the overall great lineup of Pokemon. All I know is that these three are my favorites... I really can't choose between them.

It was Gold (more recently HeartGold now), but when I discovered Pokemon White it topples my list.