actually, you can simulate the linux command terminal pretty well within windows environment.
Just download the
CygWin application and install it on your windows machine.
It will allow you to use linux commands in windows.
You mentioned that you have installed Ubuntu, but that it uses a GUI. Well, it has a Graphical User Interface, but the command line is still there, beneath all those graphics. You can easily access it by either using the shortcut combination Ctrl + Alt + T or just searching for "Terminal", that is if you are using the newest ubuntu versions with Unity. If you are still on Gnome, then just go to Applications > Accessories >Terminal.
Have fun with the command line!