I guess I'll make a list like most of you. Here it is, from best to worst.
XII, IX, VIII, XI, VI, VII, XIII, X, V, IV, X-2, III, I, II.
Yes, that is FFXI as 4th best. It was actually really awesome, from a story/lore point of view, and had some of the most fun and addicting gameplay out of all of them. Also, X-2 has some of the best combat of the series.