Clearly this wasn't Don Bluth's finest day as a filmmaker- it's nowhere near the imagination present in The Secret of NIMH and An American Tail, but it's still entertaining for kids. It certainly worked when I first saw it, and I remember watching it several times (maybe cause of the songs which were like filtered but enjoyable Elvis-type tunes, or some of the designs with the characters like the evil owls). It's about a little boy who gets transformed into a cat- his storybook, which comes to life, is about a rooster on a farm who can't do his patented COCKADOODLE call- and soon he's swept up in a quest to bring Chaunticlair back from his fall into a career as an Elvis star.
It's not really too amazing, and it's probably even cliché by the standards of any animation let alone Bluth's. But there's enough invention and fun and quirks to make it worthwhile as a children's film, if not as an overall family flick (adults will most likely enjoy the final performance of Phil Harris, the voice of Baloo). Some of it is even very funny, like when the dastardly inept small owl who keeps spouting exclamations like "ANNIHILATION!" tries to skewer the heroes while tied up. It's like a minor rockabilly farm comedy, and there's certainly worse out there for your kids.