Speaking of Jurassic Park, I just reread the book to see if it's age-appropriate for my sons (5th grade). The part where the little compy eats the baby's face off: NOT age-appropriate. Book is a lot more gruesome than the movie, so I think we'll wait.
As for holding up, I think the movie holds up much better than the book. Crichton is a very "technical" writer (vs. character development, dialogue, scene setting, etc.). Technology that was new at the time obviously isn't new anymore, like describing what a CD-ROM is or how touch screens are foreign to the characters. The overall cautionary tale holds up, just not the details. Spielberg does a much better job of telling a more "timeless" story.
Also, you get a sense of the passive sexism everyone is talking about now. For instance, in the narrative he refers to the male adult characters by last name. But he refers to Ellie Sattler by her first name, same as the kids. She spends most of the book nursing Malcolm, though she does do some adventuring in the end. In the book, Lex is just a bratty little kid. Spielberg does a much better job with the female characters. I'm certainly not saying cancel Crichton. But you kind of get a sense of that passive sexism we didn't even really notice a couple decades ago.
Anyway...that's a long-winded way of saying the movie holds up better than the book. Though both are still good.