With the release of Visual Studio 2010 the Toolbox has a filtering mechanism for the toolbox items displayed which filters only controls that target the same .NET Framework as the current project.
Having this in mind can you check if your project targets the same version of .NET Framework as the RadControls that you selected using the Toolbox Configurator? From what you have written in your post I can see that you have selected the RadControls that target .NET Framework 4.0 (this is marked using the last two digits in the assembly version). If not then you should either change the target framework of your project, or choose different version of the RadControls using the Toolbox Configurator.
If you have any further questions, please feel free to write us again.
All the best,
the Telerik team