@GeePawHill
Jurassic Park.
It took them three movies to cover all of the first book, but they did do it, and I liked the way they adapted it. Dropping that confused nonsense about fractals was a good move, too.
Firefox.
Admittedly, I haven't read the novel in many years, but I've rewatched the movie from time to time, and I've appreciated it more as I've gotten older. The final act is as fun and tense as ever, but I think they did a great job of conveying the fear, tension, paranoia and sacrifices in everything that led up to it.
I think part of the reason I like it so much is that I grew up on Bond movies, starting with Moonraker, and this feels like the darker, more realistic alter-ego.
Hellraiser.
Technically it was a novella, but I don't care. I grew up on movies and TV series that splashed their technical limitations all over the screen, so that's actually part of the charm for me. It wasn't entirely faithful, but still conveyed enough of the spirit to make me happy.
I also find it illuminating that the remake, complete with Mr Barker's approval, left me unmoved. It was in a whole other league in terms of technical execution, and Jamie Clayton's rendition of the lead cenobite was closer to the written description, but the spark was missing.