Wallpapered Bookshelves...cool looking, but I have too many books for something like this-they would get too heavy. Better to get something freestanding so I can stack them in 2, 3, or even 4 layers deep.
Painted wood floor: fill in any large gouges or scrapes, and sand the entire floor lightly. you can use nearly any paint on the floor, but if you're concerned about it rubbing off with traffic, talk to the people in the paint store/department. you can also get clear acrylic sealer to paint over the floor once it's dried and once cured, it'll protect the paint job.