Zelda Ocarina of time on N64 and Baten Kaitos on GameCube
I prefer japanese tracks, because european and american tend to be so conservative and rather dull.
In most games I tend to switch the music off because it just puts me off. Like in skyrim, it is much more realistic to travel around the contryside without any backround music. that way the ambient sounds come through and make me feel like I'm really in a middle of nature.
Unfortunately in some games the music cannot be turned off.
Worst sound track are definitely the annoying super mario tracks.