Well, mozilla is open source and not netscape... umm... uhh...
They're both ugly bloated slow and unfunctional. All there needs to know. I would go with either Camino or Firefox.
Netscape 7.2 is an implementation of Mozilla 1.7.2 with just a few customizations. Mozilla 1.7.12 is an update on this codebase. Mozilla--now known as the Mozilla Suite--continues development as SeaMonkey. The lastest version, SeaMonkey 1.1a, is equivalent to Mozilla 1.9a1. The latest developmental release of Firefox, DeerPark 1.6a1, shares the v1.9a1 codebase with SeaMonkey. The latest stable version of Firefox, Firefox 1.5b2, is based on v1.8.