PSI: Palma's theme when you're exploring. It's just happy and up-beat -- couldn't get enough of it when I was playing through the game for the first time. I also liked Dezo's theme; it gave it a sense of mystery.
PSII: Violation (when you're going through Dezo's dungeons) is good. It was kind of eerie, but it was very suiting. Again, I liked Dezo's theme in this one as well.
PSIII: So much music from this game that I loved! The main theme, Laya's hidden world, Satellite, LaShute, Anger, the ending themes...I loved all the music!
PSIV: I don't think I could list all the music I liked from PSIV, but there's many.
