Yes!
Even though you may be sharing your screen, sometimes you don't need or want to display your entire desktop.
Immediately after you click the Screen Share icon within your Live Meeting, a window will pop up asking if you'd like to share your Entire Screen or an "Application Window." Select "Application Window" to see the open applications on your computer, and if needed, choose the one that best suits your needs - perhaps there is an application that you need to demo or a website that you want to walk through. Once you've selected an application, that becomes the only part of your screen being shared.
For more information on Screen Sharing, click here.