Step 1: Download the demo for one of the following games from XBLA:

KOF98UM
GAROW MOW
SAMURAI SHODOWN II
METAL SLUG 3
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Now, download one of the 4 Games, or all of them.


Step 2: once they have finished downloading, start up MW2.

Step 3: Go into private match and start the game.

Step 4: Quick Launch one of the demos at the Private match loading screen.

Step 5: It should not give you the option to unlock full game.
You can earn achievements and play online!



I hacked a VIP account on Game-tuts. This was in there. Thought I would share. All credit to Low Gravity.