Actually, reading the credits on the dvd box helped explain one oddity of the movie. It's credited as deriving from two sources: (1) "Based on the 'Earthsea' series by Ursula K. Le Guin" and (2) "Inspired by 'Shuna's Journey' by Hayao Miyazaki". If this is right and the film brings together two separate stories, then the whole opening sequence (which doesn't come from Le Guin at all) finally makes a sort of sense.
What really made my head spin around was seeing who Disney picked as the voice talent for the English dub. Timothy Dalton? Cheech Marin? Willem DaFoe? Really? I think the voices of Cheech and Chong were about the furthest thing from my mind when reading, say, A WIZARD OF EARTHSEA. It makes me glad I don't listen to dubs much (i.e., if there's any way to avoid them -- sometimes, as when a film's shown in a theatre, there's not).
One wholly good thing about this film, though, is the beautiful, simple, haunting theme song, which I bought on dvd single soon after it came out: highly recommended, as long as you're not put off by the fact it's in Japanese.
But oh, if only the original plan years ago to have Hayao Miyazaki himself do it had come off!
*it doesn't help that the entry in the series it draws most from is TEHANU, the worst book in the series