I think music in Final Fantasy and Kingdom Hearts games are the best music in RPG games. I particulary enjoy the Jpop, and Classical music. The English songs in FF are good as well.
The music from FF 1 through 9 is unmatched thanks to the godly ness of nobuo uematsu, may his songs forever reign. Kingdom hearts also has some great beats and Revo's songs in the recent Bravely default games is just as godly.