Logan's Run. The movie is no masterpiece, but then neither is the book. And the movie is more focused. The book is episodic and at times very silly.
Make Room! Make Room! The movie (Soylent Green) is much more memorable. I've read Make Room! Make Room! and don't remember anything about it.
Four to consider (though I haven't read the original books yet, so cannot confirm):
- Jaws
- Planet of the Apes
- Who Censored Roger Rabbit/Who Framed Roger Rabbit
- Do Androids Dream of Electric Sheep/Blade Runner