Guardians of the Galaxy
Captain America: The Winter Soldier
I loved TWS, I saw it on my birthday :) But, I saw GOTG just last night and I must say, it was close, but Guardians of the Galaxy was a lot funnier.
Hard to choose, but If I had to it would be Cap because it was the more serious film, and had sense of relevance. GotG was defiantly the funnier film.