A cheat, that allows you to play tag team is this...
At the title screen with the large MK logo, hole Left and Right and press start.
Now can chose four fighters instead of one.

Some special attacks:
Lu Kang         down,forward,back,back,high kick (near to your victim)
Kung Lao        forward,forward,forward,low kick (stand within sweep range)
Johnny Cage     down,down,forward,forward,low punch (stand close)
                forward,forward,down,up,uppercut fatality, hold down
Reptile         back,back,down,low punch (stand a little bit away)
Sub Zero        hold low punch,tap back,back,down,forward

To fight Noob Saibot you need to win 50 matches in a row on a two-player game.
And at least you have to fight two different charakters.