To pick just one book is cruel. There are so many wonderful books out there and I have loved different ones throughout my life. So, I shall cheat, because asking me to pick only 1 book is not fair.
I am a huge Arthur Miller fan! You might say, he didn't write books, he wrote plays, and you would be correct, but he wrote them so well, and he did have some nonfiction books as well. I can still remember how enthralled I was when we read The Crucible in high school. That was a good play. And Death of a Salesman, took me longer to get into, but I loved it. I remember going on a date to see All my Sons just after I had finished reading the book. All of this and who wouldn't love a guy who married Marilyn Monroe?
I also am a big Mitch Albom fan. The first book of his that I read was The Five People You Meet in Heaven. I loved that book. So detailed in the descriptions of what he thought it would be like. The next book was Tuesdays with Morrie, which I also loved. Such a great message. For One More Day was my next book. I think I read that in 1 day. I couldn't put it down. His last book, Have a Little Faith was written much like his first non fiction book. It challenges you to take a look at your own faith, something that I don;t do often enough.
So there you have my cheat. There are so many other books that I can think of, but I'll stick with my favorite authors.