fixed.Progressive scan video is displayed on a per frame basis.
De-Interlaced video is displayed on a per field basis. The even and odd fields are stitched together (weaved) to create a frame.
What masta.g.86 said. In short, you always set interlacing to none on your first run. If you see your screen wobbling up and down, only then do you try out the various interlacing options.