Here are my ranks:

1. MKD (Because it's the first one I played, and the konquest felt real to me)
2. MKA (variety of characters)
3. MK vs DC (I haven't played it yet, but I saw movies on youtube and I LOVE the joker)
4. MK3
5. MKSM (I saw the fatalities in konquest, plus I like Kung Lao)

and the rest I don't care about.

1) Deadly Alliance - Best and most elaborate storyline.

2) Deception - Almost as good as DA (better in some areas), but the continuity errors in Konquest bug me.

3) MK4 - My Favorite roster and fatalities.

4) MK2 - The game that shifted the tone from "Enter the Dragon" to "wars against evil dimensions". The atmosphere is great, the finishers are perfectly animated, and all my favorite arenas are from 2.

5) Armageddon - All my favorite characters in one game. Reiko is back, Fujin is back, Sareena's finally playable...it's a beautiful thing. So why'd they have to go and screw it up with such a thin story and no REAL Fatalities? Also, I dearly miss Kombat Chess. The Kart game is friggin' useless.

6) MK vs DCU - Best graphics and gameplay in the series...but 11 characters and a non-canon story just ain't enough.

7) MK1 - Gotta give love to the classic. I so wish I could put it higher but there's no shame in losing to your own sequels.

8) MK3/Trilogy - Terrible finishers, terrible costume designs, not feeling the urban setting at all...and I never could get the hang of the god damn running and combos.

1. MK2
2. MKSM
3. MKD
4. MK3
5. MK1
6. MKA
7. MKT
8. MK4/MKG
9. MKDA
10. UMK3 (SNES version. The XBOX live arcade version does not give in ger.)
11. MKM
12. MKvsDC
The real failure of MK games is not in my list: MK Special Forces for PS1

1) Mortal Kombat Deadly Alliance
2) Mortal Kombat Armageddon
3) Mortal Kombat Unchained
4) Mortal Kombat Trilogy
5) Mortal Kombat Gold
6) Ultimate Mortal Kombat 3
7) Mortal Kombat Special Forces
8) Mortal Kombat Tournament Edition
9) Mortal Kombat 4
10) Mortal Kombat 2
11) Mortal Kombat 3
12) Mortal Kombat vs DC Universe
13) Mortal Kombat Shaolin Monks
14) Mortal Kombat Mythologies
15) Mortal Kombat Deception

Deception - This felt like the biggest and most "involved" MK game to me. Konquest was great and Chess Kombat was a neat treat I wouldn't mind seeing again.

MK 4 - I liked the dark, sinister atmosphere. This seemed like one of the most brutal and "evil" games in the series.

MK vs DC - This also seems more "involved" than the others. By which I mean, we see more of the story play out, and from different perspectives. Graphics are great, gameplay is addictive, special moves are fantastic. The only problem is that it's only got 11 of our MK friends.

MK 3/UMK 3/MKT - The urban environments were interesting, and the graphics were better than MK 2. Some new and interesting characters.

MK 2 - Also one of the more dark and evil-feeling games in the series, but I wasn't a fan of the roster.

Armageddon - Only for the huge roster and return of some of my favorites (Shinnok, Rain, Fujin, Reiko, etc.). It felt really rushed though. It was just cut-and-paste from the previous two games, with some little extras and a slightly tweaked plot.

Deadly Alliance - I really didn't like this game much. I liked the story concept, but the gameplay fell flat. It felt rather bare-bones compared to the other games. One fatality per character, an easy win with an Impale, and a lot of the returning characters lost nearly all of their special moves.

MK 1 - Great respect for this game, but compared to it's sequels, it's pretty basic and bland.

Mk2
MkTril
Mk:D
Umk3/Mk3

...and the others in whatever order as I really don't play much of the other Mks' outside of these.

MK: A
MK: D
MKT
MK4
MK2
MK1

MKD
MK2
MKDA
MKT
MK4

1) Mortal Kombat: Deception

2) Mortal Kombat 4/Gold

3) Mortal Kombat: Shaolin Monks

4) Mortal Kombat 2

5) Mortal Kombat: Deadly Alliance

6) Mortal Kombat 3/IMK3/MKT

7) Mortal Kombat vs DC

8)Mortal Kombat: Armageddon

9) Mortal Kombat 1

10) Mortal Kombat Mythologies: Sub-Zero

11) Mortal Kombat Special Forces

1. Mortal Kombat 2
2. Ultimate Mortal Kombat 3
3. Mortal Kombat Trilogy
4. Mortal Kombat 3
5: Mortal Kombat Armageddon
6: Mortal Kombat Deception
7. Mortal Kombat
8. Mortal Kombat vs DC Universe

1.MK1
2.MK2
3.MKSM
4.Deception
5.MK3 series
6.Armageddon
*a few billion MK games later*
9,999,999,999,999.MK:Special Forces