I appreciate fiction, but I almost always read nonfiction. It’s probably because I typically choose the books on topics I’m interested in, and I want to learn about them. But I also love the way a great nonfiction writer can weave a narrative so strong that it’s just as much literature as it is journalism.
Some of my favorite examples of nonfiction that do this well: Soul Full of Coal Dust, Toms River, Desert Solitaire (Abbey can be problematic, though, so be warned), The Pine Barrens, This Land, and on and on.
I guess I’m kinda stuck in the environment/nature section these days!
Fiction has always been my preference: I started reading to find my own world to take refuge in, when I was young, and fantasy, specifically, really fulfilled that need. Escapism is the main reason I still read books. I never really got into historical biographies, however I do love a good philosophy or neurolinguistics book if I am in the mood to learn something new.