Since you're just on X-mas break, I'm not sure if you'll have time for all 5 games. (Well, if it's a generous college, maybe?) But this is the order I'd do them in:
-Odin Sphere. It's a great game, and as others said, you can't go wrong with Atlus!
-Suikoden 4. It's considered by many to be the weakest link in the mainline series, but even still, its weak point is massively better than some other game you brought...
-Disgaea. If this game sucks you up, you're stopping here. And even if you don't do item worlds, it's still a great little game.
-Kingdom Hearts. At this point, we're really at the 'meh' games. The action aspects make it different, but if you're looking for more traditional, this really won't do well.
-FFX, well... that's dead-weight. I've tried playing that game. Twice. I just could not be held by it. The story was drab, the mechanics too lose, the game too easy, and the minigames frankly suck. Add in its linearity (not as bad as 13, but close), and it's just not fun to play.
-dunno001
-On a quest for the truly perfect game; I don't think it exists...
