FFVIII remains the one I look most forward to playing, though I'm not sure why.
Of the people I know that have played FF8, most of them either love or hate it with that passion spoken of earlier in this thread. I'm stuck in the middle, but here's what may make or break it for you. IMO FF8 seemed like a mixed blessing. It was fun, the card game and battle system were unique, the story was decent, and the only US game (as far as I know) to integrate Pocketstation support made it a pretty cool title.
But the socially-challenged Squall wasn't a very charismatic main character. Refining the cards into spells and items was cool too, but it yielded some crazy effects. I was a witness to my friend defeating the end boss using only the item and fight command command because he refined 100 holy wars, and was nearly incincible the whole time.
Moombas seemed like an attempt to create a creature that would be loved and embraced by the FF fanbase like moogles and chocobos, but people didn't seem to care much about them.
Then there's the deus ex machinas here and there from when the plot writers wrote themselves into a corner. "Say, we all grew up together! Isn't that something? I guess we all conveniently blocked it out because the GFs made us forget." Well do Espers make people forget too?
There's also the "level up your characters to 99 before fighting Ifrit" thing. If you have the patience to do so, more power to you. As for FF4, it's awesome, but I'm only about 4 hour into it.
I just got it for PSX a little while ago, and am planning to go through the GBA version when it comes out. I can't wait.