[CentOS] Video Recording

Hi,

I would like to record some training/advertising videos, in a similar format to those offered by CBT Nuggets (and others). Essentially this means I need to be able grab real video (e.g. webcam or DV camcorder, etc) as well as what is on the computer screen (VNC Recorder maybe) and audio.

In terms of output I would like it to be in Ogg Theora format as these seems to be supported both on Linux & Windows (though media player plugins), it is also an open standard which beats all the other available formats.

Does anyone have any suggestions for such a program, even if it is suite of different programs. My google/freshmeat search results have so far been not very useful.

Thanks in advance

Lee