Based on my understanding:
It depends on the degree of magic involved. For Harry Potter, the general view is that magic not only forms the whole theme of the movie, but the magic involved is "dark magic," thus making it unsuitable
On the other hand, Disney movies are children-friendly & cater to almost everyone. There is more emphasis on family values rather than magic. Of course, magic is featured from time to time, but it's presented in such a light-hearted way that it becomes sort of acceptable as "friendly magic"
I always believed in being balanced & rational. Hey, if you want to take things to the extreme, even Mary Poppins is a magic film & thus Christians should not watch it!
Anyway, never met anyone with such a restrictive conscience that they avoid Disney movies!