I had a terrible time finding a good desktop capturing software for Ubuntu, so thought to write a post since I don't want you to get into the same trouble. I first tried "RecordMyDesktop", it is all good other than the format it outputs! As far as I could see, it only output in ".ogv" format. But I wanted to have it in AVI/mpeg format. Then I tried to find a converter. Downloaded some converters, but converted videos were in really bad quality.
This made me to search bit more. Then I found "XVidCap" software, which saved my day! It worked really well, and I recommend you to use it! You can easily search for it in Ubuntu Software Center and install!