EDIT - A good program to capture gaming videos is Gregion. Not very easy to set up and it appears to be abandoned, but it's free and it does unlimited capturing.
It can use it's own loseless format, but you will probably have to convert it before uploading. I set it to use XVID with minimal compression then resize and compress using VirtualDub. I'm getting better results that i got with fraps, and smaller files too.
Download here: http://www.filecluster.com/Antivirus-Report/Gregion.html
