So I play Stark at and the Crown of Winter makes my Stark character immune to character ability's. My friend plays Greyjoy so intimidate is huge with him. If the character is immune to ability's does that include intimidate and can I block his character so it doesn't go uncontested?

(3.7) Card Abilities
"Card abilities" (i.e. "Character ability,"
"Location ability," or "Attachment ability")
refers to anything in a card's text box, except
for traits, keywords , and flavor text. "Card
abilities" also refers to any abilities (again,
keywords and traits are excluded) gained by
card effects

So, by this entry in the FAQ, keywords are not included in the definition of character abilities and are thus not considered character abilities. You cannot be immune to Intimidate.