Suikoden 2 imo is the best in the series and my favorite game of all time! It has an awesome story, mesmerizing sprites (especially in the intro - damn good animation), amazing gameplay mechanics, memorable characters, the list just goes on. There are too many moments just stuck in my head, as this game toyed with my emotions a lot (damn you Luca Blight and Gorudo).
I think I have beaten the game like 8 times because I loved it that much, and I have not played a game as much as it ever since (went through 20-45 hour play-throughs depending on how slow I wanted to take it). This beats any Final Fantasy ten-fold hands down!
As for music, I would say pretty much the whole soundtrack is awesome. It served as a part of my inspiration for playing guitar. I learned to play Beautiful Morning and Reminiscence. Reminiscence is so awesome I can't help but play it every time I pick up a guitar because it is fun and relaxing to play it :)