Impossible to say what game has THE best soundtrack, but here's a few that I think are really good (in no particular order):
- Chrono Trigger - Final Fantasy 4-9 - Shin Megami Tensei Nocturne - Breath of Fire 2 & 3 - Baten Kaitos series - Castlevania series - Secret of Mana - Secret of Evermore - Metroid series --- PSN - Expa0 - The official Doppelganger of SMT IV boards -
As far as 3DS goes: Probably Resident Evil: Revelations or Kid Icarus: Uprising.
In General? Mega Man X and Castlevania: Symphony of the Night have what I consider to be the best soundtracks in gaming. --- "Samuel Jackson! Made painstakingly by me, Samuel Jackson! It'll get you drunk!"
Any answer that isn't from a Falcom game is IMO wrong. --- Hardual Casuacore - The new generation of nobody-should-care-what-the-pigeon-hole-tag-is. Good games are good, bad games are bad, opinions are opinions. Period.