Only a correctly configured server can deliver VRML. Most servers now include the VRML mime-type in their default configurations. If you have an older server you will have to add the type yourself. VRML's mime-type is: x-world/x-vrml

The VRML extension is: .wrl

A VRML browser that you down-loaded should run as a plug-in. There should be no need to add the VRML mime-type to your Web-browser; the installation of the plug-in will handle that.

A version based primarily on SGI OpenInventor (in fact, a subset). 2.0, however, adds capabilities that make it distinct. Therefore, if you know 1.0, it may not help :)