Linux itself has nothing to do with those desktops. Those desktops environments are just a wrap around the command shell. They, as many others, provide a couple of tools and applications to make your navigation and administration through Linux "easier", ratter then using the command line. Personally, I found both very similar, with inefficient tools. I use Blackbox and XFCE, because they are clearly faster then those big guns...
Coming from Windows, both KDE and Gnome makes your life easier. But the true Linux power lies on the shell command, in my honest and humble opinion. Here are few other desktops that you might want to check out:
Well, most of those sites has screenshots, so you can see how much Linux desktop can vary. It's cool. There are many more, let's see if somebody else collaborate to the links