All his novels that I’ve read are boring, weird, and mystical without seeming to have a big point to them. I’d avoid them. I would , however, recommend his short stories highly . There’s a five-volume collection of all of them, which I recommend. (Most people don’t seem to realize that the movies based on his writing was almost all of them based on his short stories, not his novels.)
Hollywood has made some great movies out of his short stories (the original Blade Runner, the original Total Recall, The Terminator). But you have to realize that these movies usually have little to do with the short stories. The movies are more inspired by them than faithful adaptations of them.
This is for two reasons:
First, the stories have too little in them to make a movie out of if Hollywood was set on making a faithful adaptation of them. But this is how they like it, and why they choose the short stories rather than the books. The diretors and writers want to use a lot of creative license to fill in the gaps and flesh out some core idea that they might find interesting.
Second, Hollywood still isn't ready to make a faithful adaptation of a Philip K Dick work, because his works rarely fit the Hollywood scifi formula. They are usually too dark, too depressing, and are rarely full of action, have too much dialogue, and require too much thought on the part of the audience. Scifi blockbuster material this is not. Not unless it's heavily altered from the originals, like most of the movies based on his stories are.
Blade Runner is a notable exception. But even it is pretty superficial and action-packed compared to the book. It's still a great movie, and (in my opinion) far better than the book. But it's not as faithful as it could be.
Regarding your disdain for his books, I can understand it. They're not for everyone. I happen to like weird books, and I think Dick has points he wants to make when writing them, but you obviously missed them. And since you missed them, I don't blame you for not liking them. I wouldn't have liked them myself if I thought that they were pointless. But they're not. I could write long essays on the points of each of my favorite PKD books, but I'll spare you.
I'll just say that they are great for people who enjoy reading and thinking about the following themes:
- what is reality?
- what is the purpose of life?
- what does it mean to be human?
- is the world as it appears to be?
- what, if anything, lies beyond the appearance of the world?
- are non-human or "subhuman" lifeforms less worthy than the fully human or "superior" human beings?
- what is the role of the mass media in our world?
He was also deeply interested in mysticism, gnosticism, and philosophy, and is one of the more philosophical science fiction authors I've ever read (as you can probably tell by the many of the themes listed above). If you are interested in any of those, you'll probably like Dick's best books.