I like Secretary a lot. It shows a woman discovering her submissive side, a man afraid to be a full-time, loving dom, and how they work to make it into a lifelong D/s relationship. Very sweet, I think, and a portrayal of a healthy relationship. Although a boss who really did that would probably be arrested, it makes a nice transition from a fantasy premise to a realistic relationship. Like others have said, it doesn't show a lot of serious action. But if you can see what it implies and fill in the details with your imagination, there's a lot there.
You might like 9 1/2 Weeks. I just watched it last night. It was pretty hot (and I was pretty drunk watching it--lol). A man is in touch with his dom nature, a woman is not very in touch with her sub nature, and he seduces her, but they can't make the transition from sexual affair to loving relationship. He keeps pushing the limits faster than she's ready to move. But you'll see some neat scenes with blindfolds and humiliation. And this one, like Secretary, is one you can keep with your Disney cartoon collection. :-)