Jing - free screen video capture tool
I am a great fan of Camtasia. It is a fantastic software for making video demo of software for online streaming. It is a great tool.
However, Camtasia is a commercial program. There is a free tool that is not as powerful, but can perform the basic functions. It is call Jing. Jing is created by Techsmith which is the maker of Camtasia too.
You can get it from www.jingproject.com.
Enjoy. It is free and good.