Actually, upon even closer inspection, all the files have those artifacts but they don't seem to be normal interlacing artifacts, because they show up as these short comb-like lines along the edges of vertical lines, and they are short, regardless of the speed of the movement and they don't appear in all frames. Here's an example - these are taken from three consecutive frames, the 1st of which doesn't have the artifacts and the other two do:

http://s25.postimg.org/tpxtir21b/Jabba.png

(I doubled the size to make the artifacts clearly visible.)

EDIT: In After Effects, thwere is an Effect called Reduce Interlace Flicker, which seems to take care of these artifacts without any significant loss of detail. I'll post a sample soon, for Puggo to decide, what he'd rather have.)