To understand the film, none.
To understand the jokes, you need to watch or know X-Men Origins: Wolverine and X-Men: Days of Future Past.
Those jokes with all other references (almost) present over this movies & TV answer.
Colossus's character did appeared in X2, X-Men: The Last Stand, X-Men: Days of Future Past but none of his past role have any importance for this film and he is even played by different actor actors.