It hurt to watch this movie! It is based on the book "The Dark Is Rising", but was badly altered, it seems, in the name of making it more commercial. I have tried to wipe it from my mind, but quite a few things stayed with me:
The wonderful, caring, loving Stanton family was messed about with,
diminished, siblings chopped out and pointless conflict and hate
Merriman's character was severely diminished.
Will has an evil twin.
They became American, I guess also for marketing purposes.
Will is older, because maybe there are too many 11-year-old magic
There is a love interest.
Pretty much all the beautiful Celtic myths were chucked out - ie, the
heart of the story.
This is an interview with Susan Cooper. Please note the last lines,
"Cooper is waiting for the movie, but with a certain sadness. She says
she sent a letter requesting changes to the film's script, but she's
not sure any alterations were made."
This is one review: http://www.avclub.com/articles/the-seeker-the-dark-is-rising,3258/
This is the IMDB page, there is a fairly accurate review at the end of the page: http://www.imdb.com/title/tt0484562/?ref_=sr_1
(There is also a wikipedia page, but I'm not sure how people here feel about links to wikipedia?)
You could maybe watch it with your daughter as an exercise in how books are converted to movies, but I really wouldn't recommend it.