Actually in Sub-Zero's ending in MK2 it reveals that it is the younger Sub-Zero.

That is correct. The MK2 comic that was written by John Tobias shows Sub-Zero talking to Liu Kang and Kung Lao. Liu Kang didn't believe that he was Sub-Zero when he gave him his card, but Sub-Zero explained that he was the younger brother of the Sub-Zero who took part in Shang Tsung's tournament.

The younger Sub-Zero in the MK2 comic didn't quite seem how I would picture him, especially from the way he dressed.

I never read that comic, how did he look? Was he in a suit?

Damn what a Idiot, didn't even know that. (Joking) Yah MK2's Sub-Zero is the Young one, I'm surprised Kintaro didn't eat Sub-Zero.

In Mortal Kombat 2, Noob Saibot had been a wraith in the Netherealm working for the fallen elder god Shinnok. Noob Saibot was able to make it out of the Netherealm as a spy for the Brother Hood Of The Shadow, and his observations were to be a way of learning all of Shinnok's potential enemies weaknesses by watching and observing their battles in the shadows.