I would do porcelain tile. You'll get a better selection at local tile shops and don't be afraid to go big...I have 12x24 tiles in my 5x5 powder room.

For a first timer, I'd go with mosaic tiles no larger than 2.25 inches. They come on a mesh back in 12 by 12 sections so it's pretty easy to cut them around things, like the hole where you're toilet will set as you'll have to remove that to install any flooring, and you can cut them with a nippers instead of renting or buying a tile saw.