A couple games come to mind.
Dragon Warrior, Legend of Zelda, and SMB 3 (really 1-3) on NES
PTO II on SNES
Suikoden II, Symphony of the Night, and Final Fantasy Tactics on PSX.
Suikoden III on PS2.
Cant really say which one I’ve played through the most times. Probably one of the NES games just through sheer number of years I’ve been playing them.