Danfun128 said:
As far as I know, VHS tapes have only one audio option.
VHS does have two audio tracks, however players will only read one. When the VHS specs were first released, along one edge of the tape was the audio track, the other edge was the control track, and in-between was the video tracks in helical scan (the tracks which represent odd and even fields are pressed against each other with no space between them). Later, Hi-Fi audio was added to the VHS specification, but as I've just described every area of the tape is already used by video, the mono audio track, and the helical-scan video tracks. So in order to add the stereo audio, the hi-fi tracks were added physically underneath the helical-scan video tracks; thus they are non-continuous helical-scan tracks also. Unfortunately there is no way to select the audio, and any Hi-Fi VCR will read the Hi-Fi track (if present) instead of the mono track, however you can play the same tape in a mono VCR that does not have Hi-Fi heads and it will play the mono track and. It's very unlikely that it would differ from the Stereo track, but it's certainly not impossible.
Of course you have to have a Hi-Fi tape to begin with, and there's no guarantee that the OP's VHS tape has Hi-Fi audio if it's a really old release, in which case it will only have one audio track. If her tape does have HJi-Fi then it is possible to capture each track separately using two different VCR's.