If you press the *print screen* (PrtScr) key on your keyboard, all you are doing is putting what is called a *screen dump* of the screen into your *clipboard* - a sort of temporary memory. If you then open a word processing package like Word and press the keys *Ctrl* and *v* at the same time, this will paste the contents of that clipboard into a Word document, which can then be saved and emailed.
However, if you are trying to get a screen dump of the properties of the file when the file is open, you probably will only hear a little *beep*... you'd be better off going to Explore (right click on the Start button, bottom left of your screen), and searching until you find the file listed, then highlight the file name and right click, left click on *properties* and then press PrtScr and paste into Word as described above.