I generally like all Zelda game music, though I voted MM just because it had some mystical/creepy tunes I felt really threw you into the atmosphere, while Oot is more upbeat (though also much more memorable).
Ocarina of Time really had the best songs overall that you could play. MM really seemed to have been lazy when they made the new songs for the ocarina sound, and WW i wasn't fond of most of the songs they had.
Majora's Mask, So I could play "New Wave Bossa Nova" and summon my giant turtle and yeah...I mean cmon' it's a giant freakin' turtle that can crawl places with me on it's back! What else do you people want???
It is almost a tie for Ocarina of Time and Majora's Mask. I really like both of game's music and like the Ocarina. I would also like playing the violin (makar plays it as a cello) I like the sounds from it.
I play the Oot songs all the time on my ocarina. The song of storms and Saria's song came from that game as well which I find myself singing randomly a lot.
Easily the Ocarina from Ocarina of Time. It's an instrument not too many people hear about and it has created some of the most memorable songs in the franchise.