I, II, III, IV, VII, VIII, X, X-2, XII, XIII, Tactics Advance, Tactics A2, Dissidia
Still have to finish quite a few of them XP

FFI-had a good time with it
FFII-never got around to finish it
FFIII-hardest game ever
FFIV-fun game, and epic
FFV- love it! just havent finished it
FFVI-havent had the time to finish it
FFVII-meh...
FFVIII-f*ck you junction
FFIX-one of greatest games ive played
FFX-really sad game
FFXII-(sigh)
FFXIII- AWESOME!!

I've played...

Final Fantasy 7 ( I absolutley hated it, and I thought the graphics were bad.)
Final fantasy 8 ( I once again hated this one too)
Final fantasy 9 ( I loved ff9 and think it's the best ff)
Final fantasy 10 ( It's okay.)
Final fantasy 10-2 ( I think it's great and better than 10)
Final fantasy 12 ( ff12 is awesome!)

Weeell I've only barely played Tactics and Crystal Chronicals does Kingdom Hearts count?
buuut I just started FF 13 and its pretty awesome, I've been wanting to get into the Final Fantasy series for a long time, I haven't even seen the Advent Children movie >_<

FF III - good for an old game... Kinda drags
FFX - Was so good i wanted to play more FF!
FFX-2 - I acually haven't played this even though i have it cause im stuck on FFX
FFXII - Just got the newest one yesterday and so far it looks good lightning is a BEAST

All of them but not XI or XIV

Does Crystal Chronicles count? I played that non stop. That's the only Final Fantasy I played. xD

II, VI, VII,X,and X-2

Final Fantasy 4

Final Fantasy 5

Final Fantasy 6

Final Fantasy 7

Final Fantasy 7 Dirge of Cerberus(I despise the gameplay though)

Final Fantasy 7 Crisis Core

Final Fantasy 8

Final Fantasy 9

Final Fantasy 10

Dissidia Final Fantasy

Final Fantasy - Pretty neat; fun to play
Final Fantasy II - Extremely hard, never got past first two hours of gameplay x_x
Final Fantasy III - Like it so far, still playing
Final Fantasy VII - Favorite out of the series. Not just fightan'; had a lot of variety to gameplay
Final Fantasy VIII - Music was better than VII
Final Fantasy X - The story was pretty depressing with the whole Sin concept. Every ten years, people die?
Final Fantasy X-2 - Didn't get past first two hours of gameplay.
Final Fantasy XI - This MMORPG was not intended for American audiences.
Final Fantasy XII - Bleh. Hated it.

3, 4, 7, 8, 9, 10, 10-2, 11, 12 ,13 and several of the crystal chronicals

I started with VII, continued to VIII then went backwards but never tried the original Final Fantasy =[ Then went on to Tactics then continued with IX.
So....

Final Fantasy VII - My first Final Fantasy. Cloud's alright and Sephy is kinda overrated =[. Not my favorite either, but it introduced me to FF.
Final Fantasy VIII - One of my favorites, cause I'm a sucker for romances ;] (and Squall's awesome)
Final Fantasy VI - Also a favorite, excellent story and Kefka is probably one of the greatest FF villains ever.
Final Fantasy V - Was ok.
Final Fantasy IV - My favorite Final Fantasy game. The story is epic and Cecil is the shit.
Final Fantasy III - I liked it. Pretty interesting.
Final Fantasy II - Meh. Only good thing was the difficulty lol.
Final Fantasy Tactics - Loved it. Still play it from time to time.
Final Fantasy IX - Also a favorite, Zidane's awesome =]
Final Fantasy X - I hated this game lol. Tidus is such a wuss -_-
Final Fantasy X-2 - I got 99% completion for this game and gave up =[ Shuyin should have been the main character in FFX. I honestly would have liked FFX alot more if it was based around Shuyin's and Lenne's story.
Final Fantasy XII - so bad, I gave up before the last boss. Bad story IMO and Vaan is more of a wuss than Tidus.
Final Fantasy XIII - Lightning is hot. That is all I like from FFXIII.

On a positive note, looking forward to Final Fantasy Versus XIII and Agito XIII. From what I've seen of them, looks extremely promising.

FF I
FF II
FF III
FF IV
FF V
FF VI
FF VII
FF VII CRISIS CORE
FF VII DIRGE OF CERBERUS
FF VIII
FF IX
FF X
FF X-2
FF XI
FF XII
FF XII REVENANT WINGS
FF XIII
Actually i have all of them including the remakes.I am the biggest fan ever

Pretty much all except the Crystal Chronicles games and the MMO.

FF 1(PSP)-Fun but I lost it...
FFIV(GBA)-Fun
FFVI(GBA)-Fun and Finished(never did the superbosses)
FFVII(PS)-Fun and Finished(Did everything except superbosses and I didn't get Bahamut Zero)
FFVIII(PS)-Fun,but 4th disc was broken(Curses!)
FFIX(PS)-Fun,never finished(still have it)
FFX(PS2)-Fun Finished(left out some stuff,celestial weapons and Superbosses,just didn't care)
FFX-2-Finished(Disliked got like 80%Completion)
FFXI-Fun(got to lv 30,stopped,not enough money)
FFXII-OK(Got to Shrine place stopped-everyone usually stops here for some reason)
FFXIII-OK(Still at CH10)
FFVIICC-Fun Finished
FFVIIDoC-OK Finished

I have most of the unfinished ones still,but I'm lazy(I'll finish them on my next break)