Just few notes on my experiences with Windows open source Screen Recording Software.
When google it, Cam Studio came up top. Reading Wikipedia article was warned about viruses embedded in the Cam Studio. Found a website called LO4D.com and is safe to download from it. With Cam Studio, you can use encoder already installed on your Windows machine. Try to use the Microsoft one. Cam Studio stored recording in the AVI format which can be read by Microsoft Movie maker. By saving the video in NTSC format, you can upload it to YouTube.
I also played with Krut, which is based on Java and required install the normal JRE plus the JMF (java medial framework). The Krut worked well except that you do not have much choices on the encoder - it will output QuickTime format and a separate audio file in Microsoft format. The problem with the Krut is that when you record with 16 bit audio encoding, the VLC would complain and the audio would not play. The QuickTime seems to work fine. I suspect, you will need encoding software to make it more useful.
Another program I played is called rdp, which is also Java based. The program is at version 0.1. It worked by can't record Video and Audio at the same time yet.