May I know what visual sourcesafe explorer is and what it will do?
Visual sourcesafe explorer is the (windows only) client program most often used to communicate with visual sourcesafe databases. It has an interface that sort of looks like the explorer in windows which I suppose lead to this name.
The program allows you to interact with the visual sourcesafe database. It is considered by many to be very user unfriendly, very limited in features, and generally a pain to use. If you are not forced by violence or exorbitant pay to use it I'd stay away from it, and any job that involves using it.
If you can make your own decisions, use cvs, subversion, git, mercurial, bazar, or really anything suggested here, here, here or here.