How do I resize pictures in order to fit them all ont a cd-r?

Well here is my situation I just picked up photography as a hobby and my sister in law decided to let her family be my "testers". I did a family shoot for them and got around 300 good pictures of them and their kids. I am now trying to put them onto a cd-r 700 mb and I will only let me put on 10 pictures per cd? How do I resize the pictures with out losing quality? What software do I need to use? Thanks for the help!!!