It really depends on the type of photography you do. Fashion, architecture, reportage, etc. are usually shown in books with each photo in a polyethylene or polypro page. Landscapes and fine-art are usually shown in clam-shell boxes. The issue of whether to mount, mat or display loose depends a lot on your personal preferences and those of your intended reviewers. Many of the older, traditional landscape and fine-art photographers prefer prints to be mounted or matted as it's a more formal presentation. However, it's becoming more and more acceptable to show loose prints, especially at organized portfolio review events where time is quite limited with little room for overly aesthetic presentations.
Depending on your backing board (foam core vs. 4-ply mat board), a 2" box will hold less than than a dozen over-matted prints. You may actually get close to 2-dozen surface matted prints, and definitely more than 50 loose prints with interleaving paper. The number of prints you want to show will definitely be a factor.
Interleaving paper is a good choice for fragile print surfaces, but be aware it can become rather cumbersome to work with when time is short. Still, it may be better than having scratches.
BTW, if you intend to show loose images, be sure to include plenty of white space. It gives a more refined look compared to printing up to the paper edge.
