The prestige. Although the book is quite good in its own right. Nolan made a lot of different choices, quite a few of which are side-grades rather than up or downgrades. The movie is about ambition and competition spiralling out of control and the book is more of a quant story with a bit of a weird horror bit at the end.
The shining. Shit book, great movie. I love how Kubrick took an intentional shit on it by adapting it.
Repo men (the book was called "the repossession mambo"). One of those books that was intended to be filmed. Although the film kinda rips of oldboy and brazil, it's still an enjoyable flick.
I felt blade runner was better than "do androids dream of electric sheep".
In contrast, minority report was a made a lot worse by being filmed. They even removed the original meaning of the title from the work. Though I suppose recursive future prediction that it was about was an idea to complex for movie goers. To spoil it for the philistines that haven't read it, refers to when one of the three clairvoyant pod people sees a different future than the other two. When the main character is fingered as being a murderer by them, it sets events in motion where the prediction of him murdering that general causes him to not murder the general, which then sets events in motion where he does again for a different reason end up murdering the same general. Each of the precognition pod people saw one of those different possibilities playing out, so instead of a 2v1, it's actually a 1v1v1 future result.
In the movie they ask the question "Who is right when they disagree?" To which you get the anodyne proto-woke answer: "The woman of course".