Hmm, no, that screensaver picks a random video from the current list just like the default.
Let me try to explain again.

In the Display Menu, let's say the cursor is on NES:
-Arcade
-Atari 2600
>>>NES<<<
-Genesis
-SNES
To the right of the list, I have a video element. I
don't want it to play an NES system video. I want to play a random NES
game video. It should pick a random NES game from my library and play the video snap of that game.
If I move the cursor to Genesis, it should play a random Genesis game snap, etc.