If you have any trouble using the toolbox items in visual studio, just delete the hidden files:
toolbox.tbd, toolbox_reset.tbd, toolboxIndex.tbd, toolboxIndex_reset.tbd
in
<drive>:\Documents and Settings\<user>\Local Settings\Application Data\Microsoft\VisualStudio\<VS version>
Ex:
C:\Documents and Settings\JAVIER.VILLARREAL\Local Settings\Application Data\Microsoft\VisualStudio\8.0
Start Visual Studio, and it will reset the toolbox items in the correct form.