I think Silver has the best memories for me. Finally I had a Gameboy colour (I played Yellow and Blue on an original Grey Gameboy) and was excited about the new set of Pokemon released. You could breed in that game which added a whole new complex to Pokemon and trade them with your friends !
Right now I don't play Pokemon as much as I should. I'm more having fun with playing the TCG and playing other video games such as DOTA 2, SC 2 and random FPS or action games !
Ruby was such an excellent game! I would say it was my favorite game but SoulSilver and Emerald certainly surpass it. Groudon is one of my favorite legendaries because he is just so cool looking! He's so strong and intimidating, and besides, I tend to favor ground type pokemon in general. It's not my fault they're so rad. What are your favorite pokemon games?