How to see if a video file is progressive or interlaced?
You should be able to tell just by looking at it.  When you watch for motion and see a comb-like horizontal pattern, the video is interlaced.  You could also try pausing the video at several points and looking for this pattern, but not every frame will look interlaced.  Pause the video at points where there is quick motion, and step forward one frame at a time.  Make sure the video is displayed at %100 zoom. If you find a frame which exhibits this pattern, the whole movie is interlaced.  Once you know what to look for, you'll recognize it instantly.