Or it could be the svideo chips in the laptop. Anyone who has tried to make a media center computer and hook it to an old TV will know the headaches associated with getting a computer to output over RCA or Svideo. Generally they look like garbage. Something I read about the chips in the video "card" (I know you have a laptop and no card) are usually substandard video chips to make Svideo or RCA. After trying 3 different video cards I noticed a huge difference between quality of TV out from video card to video card. The media center community had a couple favorite cards which have decent svideo out. But you can't change that in your laptop.
Basically, RCA and Svideo outs from laptops and computers don't have very good video and generally don't look very good either. I would bet there is nothing you can do. If you wanted to, try playing a DVD video in power DVD or whatever player you have and play it full screen, I'll bet it will look decent.
But I guess it depends on your definition of "weird". If I had to describe what I saw when trying to do this. It looks like it's working and you can tell the PC's screen is being output to the Svideo/rca but it's not good enough to use. If you used the windows media center interface it would look better or playing a DVD would look better, but the PC's standard desktop is looks so bad you wouldn't want to use it.