Maybe your friend should install this[^] on his dad's Mac, and get him to use Firefox instead of Safari?

You don't need to buy any software to do this. All the following are free. DVDDecrypter to rip the VOBs from the DVD. ProjectX to demux the VOB files. Imago MPEG Muxer to remux the files to MPEG2. They can all be found at videohelp.com.