I had the same issue for a long time and wanted something simple and reliable. I found an NCH software package called 'SoundTap Streaming Audio Recorder'. I paid the $30 purchase price and was happy with the performance. It will record any sound playing on the computer.

One simple solution— make two versions with and without narration.
Sounds like you already have that capability while you search for software that will create an interactive DVD.

Mel,
My apologies I did not see your explanation of precisely your need. I don’t know if my suggestion will allow switch off of the narration.
J

Hi Mel,
I use Cyberlinks Power Director to combine photos video clips with title pages and transitions into the video section. Music can be added and narration with a microphone input.
When rendered into a combined file you can select the output type including a DVD.
I usually make a smaller digital file for a USB flash drive which plugs into the TV for viewing.
The USB drive will hold several videos depending on their size. I’ve used this software for several years now and it works well to show off our vacation photos instead of albums.
John