Well, for me choosing a favorite is just like choosing what to wear in the morning: you're never really sure.

But, some of my favs are:

FF7 (the first TRUE rpg i ever beat, and cause it's unrivaled)

FF6/FF9 (I can't pick a favorite between the two, but both have outstanding music, characters, and enviornments)

Chrono Trigger (just about the most fun i've had with an rpg)

Castlevania SOTN (incredible music (and i mean INCREDIBLE), sweet main character, amazing enviornments, super-tight controls, awesome manuevers, and just an overall INCREDIBLY ADDICTIVE game)