So, I need some thing (FOS of course) that is easy to use, supports multiple file formats, is fairly easy to install, and allows for "call outs"(ie, I can add some text and arrows on specific frames of the video). Ease of use is the primary goal here, but the text support is also required. Audio support is not required, but would be helpful. I have used CamStudio a few times on Windows, but found it quite a PITA to deal with.

Any suggestions? BTW, I am on Ubuntu, so anything with an apt package would also be really helpful.