When it comes to the breeds I would really think about getting some Barred Rocks. You won't be disappointed. They're extra friendly and great for beginners and highly entertaining. I have an issue with being scared of the chickens, but Barred Rocks, Light Brahmas, and Orpingtons have been my favorite, even my 7 year old loves them. My Rhode Island Red just wasn't friendly at all. As far as the vaccines, that's a personal choice. I don't vaccinate, but I do feed them medicated chick starter. Just remember if you do get the vaccine for cocci, don't feed medicated feed. Just in case you don't know when you order, straight run means you can get both males and females, but if you just want girls get the pullets. Here's some of my choices for hatcheries, but I'm not sure what the minimum is:
Meyer
Murray McMurray
efowl.com