Fraps: (Limited video recording but unrestricted screenshots)
http://www.fraps.com/

MWSnap 3: http://www.snapfiles.com/get/mwsnap.html

MWSnap 3 is a free program, and it's very easy to use. You simply click two or three options, and your picture is done. There's also a utility in Vista and 7 that works well. It's called 'Snipping Tool' (search it in your start menu). It's also very simple to use, though it leaves a red border around the item you've snapped.

MWSnap is really cool. http://www.snapfiles.com/get/mwsnap.html

Some screenshot software:
Lightscreen

Can be found at:
http://sourceforge.net/projects/lightscreen/