Start with the one that seems more interesting for you, among the bunch that don't look too difficult. This is the best I can say as it's not easy from a distance to guess which books you actually have. We Italians don't have such a mental power, at least not me.

If you can find a book you really want to read and have no mean to do it than in italian I would suggest you start with it. This way you probably won't be swayed from your purpose. Otherwise you can try with a copy of one of your favorite books in italian. You'll know beforehand the plot, the setting and the dialogues and you'll be able to grasp the italian way of saying the same things. Good luck! :)