Having a video, even if the app is simple, seems like a good idea. I've just finished submitting my new app to tons of review sites and it seems like some ask for some kind of link to video.
I used iShowU for my video capture. At first I was just going to record it with a video camera but the colors of the screen were all off. So I researched and thought iShowU (and just recording the iphone simulator) was the easiest/fastest solution for me. They have a trial version so if you're not sure if you'll like it just go that route :-)
If you want to see the quick video I threw together in like 40 mins see below:
YouTube - Pet Tricks Trailer (with sound)
As far as apple rejecting your app based on the website...I'm not sure they check that really. I submitted an app and my website url was messed up somehow and I'd think apple would have checked that before releasing but nope, had to change it on my own as soon as it went live.
