Lovely world and creatures, boring boring booooring generic chosen-one-must-save-the-world-there's-been-a-prophecy-and-no-one-ever-bothered-to-tell-you-before story. Complete with Mary Sue who can talk to animals and has unexpected wings and knows more than the "hero", a mentor who dies before telling the "hero" anything very useful, and random telepathy. The bad guys are (marginally) more interesting than the good guys, because at least they've got a bit of a power struggle going on. But even they are mostly irritating. As are the voice-overs and the hero's habit of talking to himself/thinking audibly.
And I feel terrible for saying all this about a Jim Henson movie, because I love him and his stuff, but it's true.
Technically, it's a masterpiece of puppetry. But as an example of story-telling, it's rubbish.