i've got a good internet connection so the you tube vid shows OS4 running it's normal fast self.
however, it would help to have audio or some other means to indicate What is going on.
it's good that you show a couple of movies running at the same time. At the meeting I attend we have run about 4 movies at once - now THAT really gets people's attention!
you should also show programs that really are visual like ZonExplorer. I believe that runs under petunia, but it still works fine and it's Very Visual. not to mention beautiful. Always a good thing when you are trying to impress people. :-D
Show a PDF. The lastest version for OS4 that I have seens looks quite good and if I recall, works fast.
run an image processing program. That is Very resource intensive and helps to show what is possible.
pulling the screen down and showing another screen is VERY good! Even better would be to show Several screens and Keep Pulling more down - THAT is what blows people's minds!
I know it's not always easy to add audio, but if you can't do that you will have to add Titles or Captions to let the view know what is happening.
good effort!