Real quick, but you probably know what I'm going to say.

Dragon Quest V - I'm playing a fanslation right now myself and this game is a classic with a capital C. It appears to have innovated many things I see games even today emulating, and I enjoy picturing a japanese gamer playing this when it just came out, as the first DQ on the SNES, and going crazy over some of the things they do. I can recommend this 100%, if you need a classic RPG, what better than DQ and you might as well play this.

Dragon Quest VIII - I think every serious fan of RPG's who's given themselves to the genre for a few years should experience this at least once. Of course, if it's not that important to you, there's really no point, right?

Metal Gear Solid 4 - can you honestly say you've really fully appreciated/understood (understood as in whole game, not just story) a Metal Gear by only beating it once? Every game I have to beat multiple times to really know my thoughts on it and how I rank it in the series. So you know you have to do this eventually.