Is Shrek a kids' movie? An animated film for adults? A demonstration of the latest computer-enabled hoodoo? A chance for DreamWorks honcho Jeffrey Katzenberg to take a poke at his former corporate masters at Disney? It's all those things, and less. Mike Myers, employing a listless version of his Scot-flavored Fat Bastard dialect, voices the title role, a grumpy ogre who lives in a swamp. He's outclassed by Eddie Murphy, who gives gusto to his comic-relief role as Shrek's donkey sidekick. The mule accompanies Shrek on a quest to fetch the imprisoned Princess Fiona (a feisty Cameron Diaz) for the vain, shrimpy Lord Farquaad (John Lithgow), who wants to marry Fiona so he can ascend to the throne. The idea is to create an old-fashioned fairy tale, complete with castles and fire-breathing dragons, and dot it with knowing winks at the whole genre. Problem is, Shrek can't make up its mind if it wants to pander to the worst instincts of kids (with a plethora of fart jokes) or adults (with mild curses such as "damn" and a recurring gag about how Farquaad's phallic-looking castle might indicate he's "compensating"). The violence may be too intense for the very wee, and viewers of all ages may be disturbed to see how close the animators who made Antz are now to replacing human actors altogether.