See the Final Fantasy page? Nobuo Uematsu composed around 90% of that (and all of it from the main series entries before Final Fantasy X), and it's what he's famous for.
Okay, Final Fantasy is great, but let's not forget Lost Odyssey, which also has music by Uematsu. Particularly, Main Theme, the dramatic, over the top, and just plan awesome A Formidable Enemy Appears!, and the soothing and emotional Prologue. There's plenty of other examples, however.
Blue Dragon, if God Himself decided to compose a song to be blasted during the Apocalypse, He would be hard-pressed to create one more Armageddon-heralding than The Seal Is Broken. That is all.
While not game related (except for one track from Final Fantasy), Nobuo's solo album Phantasmagoria is absolutely stunningly gorgeous to hear.
OC Remix's ''Black Wing Metamorphosis'', the audible equivalent to the nerdgasm? And, generally speaking, all of their Voices of the Lifestream remix album is awesome. Do yourself a favor and download it - for free - right here
"Advent: One-Winged Angel". Say what you will about the movie it's from, but that track is a masterpiece!
While Chrono Trigger was mostly composed by Yasunori Mitsuda, Uematsu did contribute some music after Mitsuda overworked himself to the point of stomach ulcers. Tyrano Lair is one of those pieces.
One-Winged Angel. The original theme from the game is memorable in of itself, but The Movie cranks it Up to Eleven with some downright badass electric guitar work.
Cloud Smiles. The way the music builds up to a crescendo as Cloud spots Aerith and then the gentleness as she turns and then the final phrase as he realises 'Daijoubu...hitori ja nai'...beautiful.
Safe and Sound, the new ending for Advent Children Complete, kicks ass way better than Calling, the original ending. It's got Gerard Freaking Way...nice tune and riffs to it too.
The End Credits track is lovely as well, an orchestral medley of FFVII's main theme, Aerith's theme and the Final Fantasy theme.