How do I convert videos for use with uDCDivx and/or Gyplay?

[TheWhiteDevil27]

Well, I want to make a selfboot movie cd to play back on my North American SEGA Sports Dreamcast but the links to most of the resources are dead. So, how do I convert video files for use with uDCDivx and/or Gyplay with sound? And where on the internet can I find a easy way to make my own selfboot movie cds for use with the Dreamcast?