Final Fantasy XI- Chains of Prometheus expansion areas. I bought the FFXI OST, haven't bought the CoP OST yet.
Persona 4 Golden - I bought and imported the disc from PlayAsia.com
Most FF games
Ni No Kuni
I love all of the numbered Final Fantasy soundtracks. I also love the music of The Legend of Dragoon, Suikoden 2, the Star Ocean series, Lufia 1 and 2, Breath of Fire 1 and 2, the Wild Arms series, and many many more. The 1st rpg track that gave me goosebumps was "One-Winged Angel" from FF7. That track caught me off guard. The choir kicks in... Sephiroth casts "Super Nova"... GOOSEBUMPS! lol
Going by memory, my favorite RPG soundtracks would consist of games such as Chrono Trigger, Chrono Cross, Dark Cloud, Okage: Shadow King, Eternal Sonata, and naturally the Final Fantasy series.
It's been a long time since I've heard music from other RPGs I've played. With that in mind, the scores have slipped from my memory. It could be that Xenosaga or even Xenogears had tremendous music, but mostly I just remember loving the voice work in Xenosaga in particular. There are couple of times I've actually owned a game soundtrack, which would include the pack-in I got back when I first bought Chrono Cross from GameStop. I did sell off my Final Fantasy IX album, but I'm pretty sure I held onto the soundtrack to Final Fantasy X. That one's a keeper.
I really don't listen to video game soundtracks with any regularity but I do use a number of tracks as ring tones for friends on my smartphone. Chrono Trigger's soundtrack has the distinction of being my favorite to assign as ringtones. So many great tracks that instantly make me feel nostalgic...