After a foiled escape attempt from the Central Park Zoo, pampered denizens Marty, Gloria, Melman, and Alex find themselves shipwrecked on the island of Madagascar. The main characters are charming, but hilarious minor players like the stowaway penguins and disaffected monkeys don't get enough screen time after the first third of Madagascar. Still, Madagascar makes good use of the tested DreamWorks formula of bathroom jokes and grown-up quips: ''I heard Tom Wolfe is speaking at Lincoln Center.... Of course we're going to throw poo at him.'' EXTRAS An amusing short about the eggnog-chugging, havoc-wreaking penguin foursome is just the beginning. The plentiful features also include a virtual tour of Madagascar, a behind-the-scenes look at the animation, and lively interviews with the film's stars. But it's too much ''Mad Mishaps'' is dull, and the ''I Like to Move It, Move It'' lemur music video is just plain annoying. The DVD-ROM, meanwhile, which offers slow-paced games and printable iron-on T-shirt transfers, is for PCs only.