The music is vastly improved from the NES versions. The only change I don't like is the reshuffled Boss music for FF2.
As for the actual playing of the games, I'd say that for a real FF1 experience, go play Origins. The difficulty of DoS is so low it's gone beyond a joke. FF2 remains almost identical to it's predecessor, so it's really up to you if you want to play it or Origins.
