If you're looking for a good, quick game, with easy leveling up, humor, and an intriguing battling system, go get Bahamut Lagoon with the translation patch. Only downside is that it is extremely linear.
FFI is great in my opinion. I didn't care for FF2/4. FF3/6 we're both excellent (since FF6 was the first Final Fantasy game I ever played). FF5 is the first game to really add interesting twists to the game with the class system and whatnot. FF7 is hands down the best. FF8 is a nice game, because it's easy to stock up on magic, which makes the rest of the game easier. FF9 is my second favorite PSX one, partially because the game is beautiful and I really liked the story line of it. FFX and XI and X-2 don't have much say in my book, as I've only played FFX. After that, my interest in FF sort of dropped.
Illusion of Gaia and Terranigma are both wonderful RPGs. Breath of Fire I and II are both some of my favorites. The Dragon Quest series has some good games in it. Any Zelda.
Oh, and I'm hurt that this hasn't been mentioned before. But Super Mario RPG? Oh, and if you have a 64, get a copy of Paper Mario. It's similar, but not quite as fun.
