A freeware tool I'm quite impressed with. It's FREE, it's easy to use and it works perfectly. You can copy videos, make your own tutorials, etc. with this simple yet powerful tool. Essentially, you just open the video you wish to copy and pause it at the very start. Open SRecorder and draw a frame around the area you wish to copy - whether full screen or otherwise. Check the "record sound:" box if you want sound, then press the red record button then start your video. When the video has finished, press the "stop button" on SRecorder and save to your choice of folder and file name. Likewise for creating a step by step of your screen for tutorials, etc.
No, it doesn't have edit capabilities or bells and whistles like Camtasia, but it's free - relatively tiny and works perfectly - link below:
Lin
http://srecorder.com/