How to enable Coop in Rayman Origins?
Solution 1:
Two 360 controllers is easy: With both 360 controllers switched on, go to Options and click player 1, hit reset. Your first 2 controllers now work.
(Was able to do this successfully with 3-4 controllers also).
Solution 2:
When the second controller is connected and recognized by the device it should say:
Player 2, press any button to join next to player 1.
On the pc version however you need to configure the controller before you can use it in the controls menu.
I have this myself game on the pc and wii and I play co-op a lot.