What I hated was attempting to mash meaning into every word in the story, even when there was obviously none intended by the author. An example I remember was when, in The Great Gatsby, it was mentioned in passing that someone had blue eyes, and the teacher went on and on about how that represented sadness, how it showed the economic differences between the classes, etc, etc. No, it meant that the eyes were blue. stop putting words in the author's mouth.
As for the kind of books that I had to read -- I found the Handmaid's Tale (Margaret Atwood) to be utterly horrid. Bad writing, large plot holes, poor continuity, etc.
To be fair, many of them (eg, A Streetcar Named Desire) I disliked simply because I found the characters distasteful and unappealing. ("meaningless people with meaningless lives")