1. I tend not to finish the ones I don't like, but I rarely regret reading. Ian Mc Ewan's "Solar" is the latest one I let go. I've been trying to finish that for ages but it just doesn't work for me.
2. Right now, "The Martian" would be on the top of my list because I'm reading it and so obviously need to know how it ends. I might also pick "The Secret History" (because I always love rereading it). Picking a third is anxiety-inducing in the same way as choosing something to read when travelling on cabin luggage only. Just thinking about it makes me want to
I might pick a grammar. Or a technical book. Or that Orson Welles biography I want to read. Or any one of the hundreds of books in my pipeline.