Saving screen image to a file? CP7

Hi,

In CP7, is there a way to save a screen shot to a file? I have a client who's users may not know how to capture a screen shot on their computer. We'd like them to be able to click a button on the slide and have an image of that slide (say certificate) be saved to a file on their pc.  Is this possible? How?

Thanks!
  Lori