I'm talking Pre-PS1/N64 days here. SNES, NES, Commodore 64, Atari.
I'd have to say Final Fantasy 6, primarily due to Uematsu's genius score within the game, the plot of characters that expanded and yet you still got to know their personal stories and there was even special unlockable cutscenes depending on who you had in your party to give even more back-story. Probably my favourite Final Fantasy game in general.
Also because one of the main characters looks like Ed from Full Metal Alchemist and their theme is probably the most epic theme ever - http://www.youtube.com/watch?v=QyPVit8Mveo