Having watched this after receiving the DVD for Christmas 2005, I came here to pan it -- but after reading the other comments, I haven't the heart. Clearly this is a film that has worked very well for children of a certain age. Well, let me not be a complete Grinch; it might still work for some children -- if they are not too media-saturated and have not become visually over-sophisticated, e.g. from watching all of LOTR and Harry Potter. But if you are an adult, stay miles away; you will not enjoy it.
The good bits: Barbara Kellerman as the Witch, especially in her early scenes with Edmund, creates just the right blend of charismatic evil and restrained madness. (At the Stone Table she goes a bit over the top.) Michael Aldridge in the minor role of the Professor and Jeffrey S. Perry as Mr. Tumnus also have the kind of polished, skillful acting we'd expect from the very best BBC dramas. And the Aslan costume works very well, amazingly well considering. They got the eyes just right.
The bad bits: almost everything else, but two areas in particular. One, the casting. England is crammed with good actors and contains tens of thousands of attractive British school kids. How could they possibly have ended up with these four stiffs? They move like wooden soldiers and speak about as well. Peter has no gravitas or charisma (and is visibly shorter than his supposedly younger siblings); Edmund is just whiny; and Lucy... Sophie Wilcox as Lucy is so dramatically, visibly, drastically wrong for this part that I can't imagine how she got the job.
Two, the animal costumes. Again, it appears that they worked for some kids. If the kids are still at a level where Big Bird and Elmo are exciting, believable characters, they might be entranced by this film. But to a viewer with the sophistication of, say, a 12-year-old who's seen Prisoner Of Azkaban? When Mister Beaver comes out from behind that tree, there will be hoots of cruel, derisive laughter. The costumes just do not work -- I could not, and I think any adult or modern teen could not, suspend disbelief when looking at Mister Beaver. The drawn animation later (gryphons, etc.) works better, is easier to take.
So: ten stars for the very young and tender of soul; everyone else read, or re-read the book and watch the far better film that unrolls in your imagination.