Yeah Kentucky. there's about four different versions of SilverLight that Windows Update notify everyone about, but just right-click on each one as they appear and use the option that you want to hide the update. After you get to about the fourth version of SilverLight and have opted to hide them all from appearing ever again through Windows / Microsoft Update, they will no longer annoy you.
Kind Regards,
Neil
PS: It's just Microsoft's version of Adobe Flash and from memory it's an optional update only.