@jordanlund I prefer the 5x8" book size, and I think that'll work really well for your lil library.
Unfortunately, if you were to go with my favourite book series, Wheel of Time, that'd be all you have room for.
So... Winnie the Pooh, Muddleheaded Wombat, Looking for Alibrandi, some Animorphs, maybe Tomorrow When the War Began, Fairytales for Wilde Girls.