I had a pet-sitting job back when I was in high school. The cat I looked after really loved the Food Channel. Bright, vivid colors, and just enough motion to keep the cat interested. It fucking loved Iron Chef and would try to grab the food as it was chopped or boiling in pots.
My mom does this for her birds. Ironically they also like to watch videos of birds. Or... or maybe that's not ironic. I'll be honest, the internet has ruined by ability to discern what is and is not ironic.
One of my cats would get totally freaked out by the dvd screen saver (a colored moving ball). She would hiss at it and keep checking behind the tv to see if anything was there. The only other av related thing they cared about was the sound of cats meowing on youtube videos.