I'm sure this question has been done before, but I'm pretty sure it didn't have a poll, so now we know which one is loved the most. For me it was Pokemon Red/Blue. Loved it, maybe it was because I was there as a kid throughout its lifespan, but I loved every second of it.

I've got to go for Red/Blue. I loved that game. It was fantastic.

R/B

Silver/Gold. It was everyhing I loved about the first game, but longer and with more and more interesting Pokemon. Plus, it had an art style to it that wasn't just a straight anime rip and some cool shading going into the sprites, AND a whole second island AND a day/night cycle.
 
yeah, man.

Red/Blue i was the right age for it back then.

Gold/Silver/Crystal were the best. They took the concepts of R/B/Y, and expanded upon them in intelligent ways. And also, you fought Red at the very end, and he had a level 87 pikachu. Which I considered awesome at the age of 10.

G/S/C.
Took everything good about R/B/Y and expanded on it.
R/S/E was actually a downgrade as far as features go.
D/P/P had some neat features, but the designs sucked.

" Gold/Silver/Crystal were the best. They took the concepts of R/B/Y, and expanded upon them in intelligent ways. And also, you fought Red at the very end, and he had a level 87 pikachu. Which I considered awesome at the age of 10. "

I prefer the remake of the originals Leaf Green/Fire Red.