I was asked what my favorite OSTs are, and I said I'd have to think about it. Here they are:

1. Final Fantasy VII
2. Ōkami
3. Chrono Trigger
4. Tales of Legendia
5. Loco Roco 2
6. Final Fantasy IX
7. We ♥ Katamari / Katamari Damacy
8. Chrono Cross
9. Wild ARMs
10. SaGa Frontier

Honorable Mentions:
Shadow of the Colossus and Total Annihilation. I liked the battle songs a lot, but the "peaceful" music was pretty shitty.

And for the hell of it, favorite battle themes:

1. The Man With the Machine Gun from Final Fantasy VIII
2. Battle 1 from Final Fantasy IX from Dissidia Final Fantasy
3. Battle Artist from Tales of Legendia
4. Fighting from Final Fantasy VII
5. Pretty much any battle music from Total Annihilation
6. Don't Be Afraid from Final Fantasy VIII
7. Fight Against Monsters from Super Mario RPG
8. Take Up the Cross from Tales of Phantasia
9. Combat from Crisis Core: Final Fantasy VII
10. Battle 1 from Final Fantasy III from Dissidia 012 Final Fantasy

And boss battles:

1. Battle 2 from Final Fantasy III
2. A Despair-Filled Farewell from Shadow of the Colossus
3. Dark Saint from Lost Odyssey
4. J-E-N-O-V-A from Final Fantasy VII
5. Influence of Deep from Parasite Eve
6. Esper Battle from Final Fantasy XII
7. Seymour Battle from Final Fantasy X
8. A Formidable Enemy Appears! from Lost Odyssey
9. Fighting of the Spirit from Tales of Phantasia
10. Still More Fighting from Final Fantasy VII / Battle with Magus from Chrono Trigger

Final boss battle:

1. The Sun Rises from Ōkami
2. One-Winged Angel from Final Fantasy VII
3. World Revolution from Chrono Trigger
4. The Extreme from Final Fantasy VIII
5. Decisive Battle from Final Fantasy X
6. The Birth of God from Final Fantasy VII
7. Howl of the Departed from Lost Odyssey
8. Time to Raise the Cross from Tales of the Abyss
9. Fight Against Smithy from Super Mario RPG
10. Battle ZEIK from Wild ARMs

Fuck it. World map/field (for those games that don't have a world map):

1. The Legend of Zelda Theme from the Zelda series
2. Wind Scene from Chrono Trigger
3. Corridors of Time from Chrono Trigger
4. Terra from Final Fantasy VI
5. Shore Bordering Another World from Chrono Cross
6. Raising a Curtain from Tales of Phantasia
7. Final Fantasy IV Main Theme from Final Fantasy IV
8. Blue Fields from Final Fantasy VIII
9. Hyrule Field Main Theme from The Legend of Zelda: Twilight Princess
10. Shinshuu Plains from Ōkami

Town theme:

1. Birth of the People from Actraiser
2. Home Sweet Home from Final Fantasy V
3. Morle from Tales of Eternia
4. Dear My Country from SaGa Frontier
5. Kingdom Baron from Final Fantasy IV
6. Another Termina from Chrono Cross
7. Seiankyou Commoners' Quarter from Ōkami
8. Town / Marsh Where the Migrant Birds Gather from Wild ARMs
9. Serenade of Elves from Tales of Symphonia
10. Kingdom of Ixa'taki from Skies of Arcadia

Character theme song:

1. Cid's Theme from Final Fantasy VII
2. Frog's Theme from Chrono Trigger
3. Kefka from Final Fantasy VI
4. Cyan from Final Fantasy VI
5. Tamaya's Theme from Ōkami
6. bucho mio ~LocoRoco Green's Theme~ from LocoRoco
7. Quina's Theme from Final Fantasy IX
8. Rose of May from Final Fantasy IX
9. Mog from Final Fantasy VI
10. The Eight Dog Warriors' Theme from Ōkami

Vehicular mechanism:

1. Highwind Takes to the Skies from Final Fantasy VII
2. Voyage - Home World from Chrono Cross
3. The Huge Battleship Invincible from Final Fantasy III
4. Wings of Hope from Tales of the Abyss
5. The Dragon Spreads Its Winds from Final Fantasy V
6. Ride On from Final Fantasy VIII
7. The Bird Which Flies in the Skies from Wild ARMs
8. Chronomantic from Chrono Cross
9. The Airship, Hildagaldy from Final Fantasy IX
10. Epoch ~Wings that Cross Time~ from Chrono Trigger

And finally, chocobo themes:

1. Brass de Chocobo from Final Fantasy X
2. Swing de Chocobo from Distant Worlds
3. Techno de Chocobo from Final Fantasy VI
4. Electric de Chocobo from Final Fantasy VII
5. Fiddle de Chocobo from Final Fantasy VII
6. Mambo de Chocobo from Final Fantasy V
7. Chocobo ~FFXII Version~ from Final Fantasy XII
8. Mods de Chocobo from Final Fantasy VIII
9. Chocobo FFXII Arrange Ver. 1 from Final Fantasy XII
10. Samba de Chocobo! from Final Fantasy IV

Man, this was really difficult. There are so many songs that I love but just couldn't fit onto the list. So if you're surprised something isn't on there, it's probably number twelve or thirteen. And even now that I've just finished it, I think to myself that some of these lists just don't feel right. My mind's always changing.

But it really brings to light what you like and what is actually good. People say there's no right or wrong in opinion, but I think you can make an objective case that Lost Odyssey's Never-Ending Journey is better than Chrono Trigger's Wind Scene in terms of sound — one is from a 16-bit system for God's sake — but I just like the latter better due to nostalgia and the theme is catchier for me.