Nero 7 comes with the Nero Scout media library application, and I couldn’t find an option to not install it (or to uninstall it later). It adds an extra icon in My Computer, and presumably runs all the time consuming system resources. The fix seems to be to run the following command (from Start -> Run):

regsvr32 /u “%COMMONPROGRAMFILES%\Ahead\Lib\MediaLibraryNSE.dll”