Pick whatever is true and gives insight into your personality. Facebook may be true, but does it say much about you? Not really. Pick something with more character. I'm putting a classical recording for mine. And my favorite movie is a silent film. And yes, those books are great. I would worry less about not seeming pretentious and more about providing a glimpse into who you are. If all these little things seem to fit together to form a cohesive picture, they won't think you're lying.