That command can also be toggled in the
Tinkertool.app application. It's the same as in Terminal, but not via command line, but via User Interface.
You can then quit Finder with CMD+Q or Finder > Quit Finder. If you quit it via the Dock however, it'll auto-restart.
Now, Mac OS X has the build-in problem that is has to have opened at least one application. So you can open, say, Pages or Pathfinder without having opened Finder.
However, if you close the last application you have opened, Finder automatically fills in the blank screen.
To finish this post:
Finder.app is the finder windows, but also your desktop. It does not cover your dock, and Saving/Opening dialogs are not part of Finder.
Hope I gave you some useful information.