In no particular order

Angela's Ashes- its a story of an Irish immigrant family seen through the eyes of their oldest son. It's ridiculously sad, but at the same time the writing makes me crack up through my tears. Absolutely one of the best books I've ever read.

East of Eden- definitely my favorite Steinbeck book. I loved Steinbeck growing up, and I think that this was definitely his masterpiece.

The Old Man and the Sea- when I first read this book as a kid I thought, "well this is boring". Several years later, when I reread it for a paper I was writing, I understood Hemingway much more, his style was fantastic and I fell in love with the book immediately.

The Harry Potter Series- simply because I grew up with the books, and it's had such a large impact on my generation. Rowling is the reason I loved reading as a teenager and the reason I love all of these other books. I absolutely love the story and reread the series once every few years.

I can't think of a fifth one right now, I'll come back and edit this post when I figure one out