I agree that the Lord of the Rings movies were better than the book. And I read the books first, BTW. I got them after reading the Chronicles of Thomas Covenant, having heard it was kinda similar...and was disappointed. Too much pointless wandering off the trail for the characters for me.
Blade Runner is another, though it wasn't that much like Androids Dream of Electric Sheep any way. They had little to do with one another. I liked the original movie better than the Director's Cut.
One thing of interest. I hated the Star Wars prequels, but the book for Episode 3 (which was based on the movie rather than the other way around) was WAY better than the movie. I actually gave a crap about the characters in the book and every thing!
IsaacJ