Camstudio is a great piece of open-source software for screen recording, but Microsoft’s Windows Media Encoder is a much more user friendly and consistent piece of software. I recommend using it for making recordings due to both it’s ease of use and file size (about 5x smaller than the camstudio produced moves = 5x shorter upload times!).
It is free as long as you have a genuine copy of Windows.
Konstantin Vlasenko 