Kalzium tutorial

After two days of work , Kalzium tutorial in Bengali is ready. You can download it from here. Yesterday night, I gave more than 25 takes on this, either sound is not coming properly, or some problem in mixing. I need a good app which can help me in the process of dubbing the tutorials. The video is in ogg theora format, audio can I get in any format. Can anyone please point me to some good app?

Recordmydesktop is rocking as far as the video is concerned, but the sound mixing is not working properly.