Michael Crichton's original novel is excellent, and if you've never read it, I recommend it highly. I find it to be the kind of novel that I can start and read straight through without stopping. I did that when I first got it, and I still do now, though I've read it 20 times or more and I know what's coming.
I read it when it was first published, and I thought to myself, "This would make a great movie, if only they could figure out how to animate the dinosaurs realistically."
Crichton drew on the latest interpretations of the fossils, and the work of both Jack Horner and Bob Bakker had a strong influence on his depictions of the animals and descriptions of the science.
Spielberg's movie came out a couple years later, and I saw it, and I was disappointed. The animation was outstanding, with new techniques and technologies used, both in terms of computer generation and in terms of models. But the changes he made to the story ruined it. Grant loved children, for example, because they shared his love of dinosaurs. And in the novel, Hammond is not a kindly little elf of a man, but an arrogant ***, who gets his come-uppance, for screwing with Nature.
I thought to myself, "If they just took out all the human scenes, this would be great!" And then a couple years later, the BBC brought out "Walking With Dinosaurs", which was pretty much that-a nature show about prehistorical animals.
As far as the sequels go, Crichton hadn't planned on writing one, but he was encouraged to do so by the studio. And it shows. Though the novel is relatively fast-paced, the story is pretty much more of the same. And it bears little relationship to the movie, apart from some characters and dinosaurs. I did enjoy Pete Postlethwaite as Roland the game hunter, though.
And the sequels got worse from there, in my opinion. I know there are millions who disagree, but it is what it is.
I've seen the "Lost World" reboot series, and they're entertaining adventure flicks, pretty much, but again, they're formula.
I haven't seen this latest one yet. I was going to pay to see it in the theater when it premiered, but then decided it wasn't worth the price to do so. I'll wait till it's streaming or on cable, on DVD, etc.