If you're using an ATi card, the .NET Framework displays the GUI for the Catalyst Control Center. FYI, Sony Sound Forge also uses the .NET Framework. There are a few versions, namely 1.1,2.0 and 3.0. You can install all 3 of them with little or no issues.
For more info, read this article.
http://en.wikipedia.org/wiki/.NET_Framework

Hope that helps.