Most of the remakes are usually based on the new interpretation of the newest creators making the movie. Their are some directors that take movie versions in completely new directions & then there are some that try to copy the old and add their own visions(Wonka/Planet of the Apes), then there is the third(example Psycho) following the script and frame precisely as the original.
Tim Burton's Alice in Wonderland coming up: the way he is doing it astounds me, because he is taking the book and bringing it to life; being true to the proportions of the characters, their looks(a la Burton style) & their environments. My jaw dropped when I looked at the new pics for the movie: the head size of the Queen of Hearts, Alice is finally showing her size in adjacent to the others, the detailing of the flowers in the garden, etc...I am looking forward to this a lot, Alice in Wonderland/Looking Glass is my favorite book.
As far as Neverending Story being remade, unless the creative movie makers behind it follow the book precisely, the movie should be left alone. I had this argument with my dad over 20 years ago when the movie came out & we compared it to the book version. Unless Tim Burton, or another director of sci-fi can interpret the book correctly into film form, I believe it would just be another remade/remake/copy of an old film.