I love the old black and whites with Cary Grant, Katharine Hepburn, Jimmy Stewart, Myrna Loy and William Powell, etc. They're calming because there's not a lot of action. There's usually a display of morals, a happy ending, and the bad guy gets screwed or has a change of heart. I also love comedies like Superbad that are just stupidly funny.

I like action movies like Iron Man, Avengers, the Transporter, etc, but they're not calming for me. They make me pretty wired.