What's it worth?

So I've had a couple of books in my possession for so long that I actually have no idea where I even got them from. They seem so old and fragile to me that I keep them wrapped in bubble wrap in a small box out of the light. I am curious if anyone might know anything about or even what they are worth. I mean, should I keep them locked away like a hidden treasure? Or put them in my library on display?

I also have this note that I have no idea about. 

Any help on any of these is greatly appreciated.

Also, don't forget the awesome giveaway from PageHabit.