You will need to take advantage of the registry for this one. Go to Start > Run > regedit.
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\. Go through all the keys until you locate the Norton Security Scan. On the right side all the strings will load. There should be one called UninstalString or Silent/Quiet Uninstall. Copy that command and paste it in Run and it should uninstall without interaction.