This is a pretty swell movie, although it helps to have some nodding familiarity with Disney-style animation involving princesses, evil stepmothers, and dashing heroes. Since I went to those movies when I was a kid, and viewed many of them with my own kids, I eminently qualify.
The story is of Giselle, a happy dweller in a woodland cottage assisted by a live-in menagerie of critters: birds, rodents, the usual suspects. In the normal course of things, she would make any dashing prince a fine wife and they would live happily ever after, or at least until Disney decided to squeeze some more money out of that particular franchise with a sequel.
But the villain here comes up with an unusually fiendish plan: Giselle is transported into modern New York City, and turned into Amy Adams in the process. Plucky Giselle retains her ebullient optimism, and also has the ability to beguile Manhattan's wildlife and its citizenry into cooperating with her fairy-tale outlook. She's not as dumb as she looks, or acts, it turns out.
This is a clever idea, and it's executed with a lot of wit and creativity. All the actors are perfectly cast. (Well, with the possible exception of Patrick Dempsey, who's the perpetual straight man as all the fantasy explodes around him; he's a little slack-jawed, maybe a little too pretty. But I'm quibbling.)
In short, a movie you can take the kids to, or not. It's a lot of fun either way.