On my MacBook, I frequently end up with lots of overlapping windows on the screen, obscuring the desktop. I recently discovered the five finger 'swipe outwards' gesture that displays the desktop. Unfortunately this doesn't do exactly what I want; as soon as I select an application (typically a Finder window) from the dock, all the windows swipe back into place. Normally I am wanting to copy a file to/from a Finder window that's already open, via drag-and-drop, to the desktop - but I can't do this as the desktop is once again obscured.
Are there any other shortcuts which could help me? For example, minimize/hide all windows to show the desktop?
I should add I'm using OS X 10.8, if it's relevant.

