Screencast-O-Matic is a desktop application that can capture movies of your screen action. You do have to create an account but it is free. The free option lets you record up to 15 minutes of a screen recording.
Click on the Screecast-O-Matic icon above to be taken to the website and explore the possibilities.
Click on this link to see the Screencast-O-Matic User Guides (located at their website).