MK1:Sonya Leg Grab
MK1: Raiden Torpedo
MK1: Johnny Cage Ball Breaker
MK2: Kung Lao Whirlwind Spin
MK2: Johnny Cage Shadow Uppercut
MK3: Sektor Homing Missile
MK3:: Kabal Spin
UMK3: Stryker Rapid Fire Gun
MK4:Fujin Whirlwind Spin
Thats All i can Think of i would like Back

Scorpion: Fire Breath (MK4)

I want Noobs disabler fireball from MKT!!I loved using that move and unleashing ridiculously long combos.AHHH the memories.

Sub-Zero's old school ice clone which could be performed at anytime.
Raiden's reverse lighting bolt...just because...
Shang Tsung triple fireballs (the regular ones and the ones from the ground).
Cyrax's net move.
Noob Saibot's kicking combo (if you'd consider that a special move).
Rain's control orb.
Can't think of much more. I just hope they give people who've had lame special moves better ones. And hopefully Shinnok has his own moves this time, I hated him in MK4/Gold...except for his fatalities...they were OK.

Well this thread has become mostly repeats, but to kill another minute or two, I'll put down the moves I'd like to see come back.
Sonya:
Leg Grab
Ring Toss
Flip Kick
Leg Grab Fatality from MK4
Kitana:
Unlimited Fan Toss
Fan Wave (A useful Fan Wave)
Square Wave Punch
Pretty Kick
Kung Lao:
Hat Throw (With unlimited mobility)
Whirlwind Spin
Dive Kick
Cyrax:
Net
Sub-Zero
Ice Clone
Ice Shower
Ground Greeze
Sindel:
Hair Throw
Scream
Fireball
Styker:
Baton Toss
....yeah

The moves that I think should really comeback are:
Kitana~Fan throw
Although they had this in MKDA it sytill was kinda pointless only because it was to imaple so it dind't comeback to her =( by having it comeback it'll be a realyl kewl look being able to do it in the air like in the old MK games
Sonya~Bicycle kick
One of my favorites in MKTrilogy, this really needs to come back, I think it looks so kewl too. PLus I liked the little Xena call she makes when she does it
Sonya:Leg Grab
I really like this grab of SOnya's she was one of the rares that had two throws and this one looked really kewl
Sindel: Hair Throw
I loved when she threw people with her hair! and it was so usefull and face and eye catching!
Sindel:Gliding
I think Sindel should be able to glide like she did in the otehr games, I luiked this one and she was the only one that could glide!

That list plus Sindel's Fly.
She looked godlike when she flew.

Reptile must get all his moves back!!!
Sindel needs her hair back and flying abilities!!
all sub zero's moves....

Yeah, Sonyas Leg grab is a must.
I also wanted to add that characters like Jarek and the others should get, most then anything, new special moves. No need for Kano, Kira and Jarek to share 1 special move. Kira is another who need a tital revamp.

I hope Kung Lao's Whirlwind Kicks are back. I just bought platinum DA a couple of days ago and I had no idea about this move. I think it's a compliment to the bicycle kick Liu Kang has and is original in its own way.
Kung Lao must have more moves though, as he only had two in DA. The teleport should return though I don't think the dive kicks are necessary now. The spin would be too much like Ashrah and Fujin now to come back, I think Kung Lao needs a new move.
I also love Shang's 3-d fire moves and want to see these return. If only he could morph again...
Drahmin's uppercut looks a bit too Dragon Punch-ish, though the juggles were fun with it.

Sindel:Hair Throw, Levitate
Sonya:Leg Grab
Sub-Zero:Ground Freeze
Scorpion:Chest Spear
Sheeva:Stomp
Jax:Ground Hit
Kitana:Fan Throw
Cyrax:Green Net Grab
Smoke:Smoke Bomb

the good moves

johnny cage: mk1 fireball and mk2 fireballs
lui kang:mk1 uppercut fatality (but as a combo) kano: headbutt
bring inpales back but instead of the weapon staying in the enemy's body they could pull it out using the same buttons to get the stage weapons and fight with it

scorpion's skullfire attack

( Depending on Human or Cyborg) Smoke: Chest Spear(Cyborg), Spear(human)
Sub-Zero: Ice Shaker, Freeze Ball
Jax: Piston Punch
and Baraka's chop Chop Blades.