Press Ctrl+Alt+PrtSc and you will have a screenshot of the current window in your clipboard. You can then paste that into Photoshop or whatever you use to edit your bitmaps.
I ask because I use a Dell. With my laptop to do a SS, I have to use the 'fn' + 'prntscrn'. On my machine the 'fn' is between the windows key and the prnt scrn is the f11.