I replayed the original Final Fantasy not too long ago and had obscene amounts of fun with it... though I have no idea why.  It should have bored me to tears.

Anywho, it's a toss up between 1, 4, 5, 6, 7, 8, and 9.  I liked each for different reasons.

FFVI

For me the best are ,in this order.

Final Fantasy VII
Final Fantasy X
Final Fantasy VIII
Final Fantasy VI
Final Fantasy XII
Final Fantasy IX
Final Fantasy V

Because that will impact your current favorite FF?

I have played trough FF3.4.5.6.7.8.9.10.(11 you cant finish online game) and 12. My favorite game is FF7. I have tried to play trough the first games so many times without sucess.

I really don't know if Final Fantasy IX is the best, surely not, but I can say that is a jewel. I love it.

Top 3:

VIII
VI
X

Bottom 3:
VII
XII
X-2

VIII for me.

The best way to summarise this discussion is 'Another mans food is another mans poison'. I think this is one endearing factor of the FF series. Each one seems to have its own distinct personality and attracts a certain type of fan but keeping the overall epic JRPG formula.

1. VII .2. Tactics .3. VI

Final Fantasy 6.