Religion is pretty complicated in Dune, it's not really resistance of Islam as much as it's pretty much all of old earths major religions were all incorporated together into one big religion that also included the basics of the Butlerian jihad against the thinking machines. Religion wasn't as much belief in a single god but a way to keep humanity more of on the same page with one another and sharing a basic set of social norms. Who sections of the universe were agnostic, the mentats, the spacing guild, even the ruling classes. The bene gesserit actually manipulated religions on the worlds to keep themselves in power and to steer humanity toward the goals they had. Then you had Paul, who'll declare himself the god emperor of dune and let lose a jihad that will scorch hundreds of worlds and lead to the biggest migration in history of people fleeing his empire and religion (his plan all along was to expand humanity to the additional worlds to keep us from being wiped out).
They first movie was as close to the original novel as any I've seen, I'll watch the new adaptation but I know I wont like it as much.
If you've never read the books, try it, they're great, the prequels, house books and sequel books his son wrote do a good job of expanding the history of the universe based off his dads notes as well as moving the story to a conclusion.
