This list does not include FFI, FFII, FFIII, FFV, FFX-2, or any of the other side FFs (Tatics, Adventure, etc.)
1.) Final Fantasy VI - Great gameplay (Esper system can't be beat), Awesome graphics (for it's time), Incredible Story and Characters. A must play for any RPG fan.
2.) Final Fantasy IX - It's tough to rank this one second and if I could have ties, it would be right up there with VI. Many people didn't like going back to the "old-school" FF style. I welcomed it with open arms.
3.) Final Fantasy X - As much as I hated many of the characters (Yuna was especially annoying), the story and overall feel of the game made me like this more than any of the other games on the list. And while many people bad mouth it, I love Blitzball.
4.) Final Fantasy VIII - Underrated. This game has one of the best soundtracks in video game history, a great love story, and a good gameplay system (GFs, I liked them anyway). The one problem I have (a lot of people have) is that the last Disc felt rushed.
5.) Final Fantasy IV - People love this game...I felt it was okay. I couldn't get into the story much. I also didn't like how when one character leaves, another conveniently takes his place. It destroys the flow of the game.
6.) Final Fantasy VII - This game does not deserve the praise it gets. It's a good game, but not the end all-be all of RPGs. Far from it. The story is confusing, the graphics are terrible (even by early PS1 standards), and the characters are stereotypical and one dimensional. It has a few saving graces, that being it's great gameplay, awesome soundtrack, and good villains (the few characters I liked). But it is by no means the perfect game. 7 out of 10 tops.