ABC said:

That's what I tried:

OK, forget the tick (check) boxes - they are not relevant to demuxing, sorry about the misinformation.

You see in your screenshot above, the video stream is the one selected (the grey highlighting is around the "0xE0 - Video" text). You need to click on the text that says "0x81 - Audio", then demux. After the operation is complete, do the same for the PCM audio stream "0xA0".

You should end up with an IFO file, a stream information TXT file and the two demuxed audio files.