Apple keyboard questions

I just bought the Apple wired keyboard for my Mac, and i absolutely love it. I am using it in Windows XP with Bootcamp, and i have noticed that certain things on it don't work. For example, the # pad on the far right, Windows doesn't recognize. And also, when i'm playing music through iTunes, the next, play, and back buttons at the top don't work either. I don't really care about the itunes buttons, but i do about the numbers, what could be the thing with them?