How to change the aspect ratio in Handbrake without pulling your hair out

[davexnet]

Assume you have a video of 1280x720, 1:1 pixels, 16/9 display.

But the video is stretched and really should be played back at 960x720 (4:3)

For the situation where you want to reencode the video to 960x720 set the options like so.
Deselect "Automatic"
Deselect "Optimal Size"
Set "Display Size" to 960
Set "Scaled Size" to 960x720

[Alwyn]

Good job Dave, that tab is a nightmare for the uninitiated.