The application that is presenting our online demos is a rather complex one and I believe it will be a better idea if you start with simpler applications until you feel comfortable with the Silverlight platform. A good starting point is the learning section of the official Silverlight website
, where you can find an abundance of learning resources. You can also check the two templates that you get when you install the Silverlight tools for Visual Studio - Silverlight Navigation Application and Silverlight Business Application.
I hope I was able to point you in the right direction.
the Telerik team