Well first of all, I must say, WW is the best Zelda Soundtrack ever to exist. In my opinion. But my favorite song was Makar's song. I can't believe I can't remember the name. But anyways, that was a great duet with Link and Makar. Also, I love the song that the game plays whenever you beat a temple boss. I don't know if you would count it a song, but it's still really cool. My favorite boss battle music is Molgera.
There are a lot that I love from this game. My favourite one is the Staff Credits music. It's so calming and catching. The Molgera battle music is amazing. It fits the fight perfectly. Dragon Roost Island's music is nice, and I love the Legendary Hero music. =P
The Mini-Boss theme for sure. I mean, when that Darknut just comes to life in the Tower of the Gods the bells really reflect the ferocity of the fight.
The "Dragon Roost Island" track has always been my favorite from WW.
I could listen to it for hours... o3o
But I really can't think of any music I dislike in WW; it had an /amazing/ soundtrack.