Everyone, really, has their own views about these games. I personally can't believe why the hell so many people rant about FF8 if that game was so outstanding!!!
But in what most agree, is that FF7 has got the best storyline, and that's what I think as well.
I;d just suggest to play them in the order they came out (basically, what you said
![Right tongue](images/smilies/righttongue.gif)
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Don't miss FF9 either. Although it may not be as awsome as the previews 2, it's still a wonderful game, has a good storyline as well, and the gameplay is slightly better than in the other 2 games IMO.
And hell, yeah, I hated FFX's end with the heart, it was too sad, and too stupid also, I would say.