@ Becco_UK: *You shouldn't need to press either Control or Alt to grab the screen. Just pressing Print Scrn on my keyboard works fine.
*Actually that's not strictly true!!

Print Screen will give you a screen dump of the screen as you see it, however:I work usually with 3 or 4 open windows either cascaded or tiled across my desktop and pressing "print screen" gives me a complete dump of the screen with all 4 open windows. 
If I press "ALT" and print screen that gives me a screen dump of "JUST" my active window and not the entire screen. Try it for yourself!

Admittedly if using Poser or Vue I only have one window open so it doesn't apply then!

Injustice will be avenged.
Cofiwch Dryweryn.