I have updated SC yet again. 2.6.4 will allow you to disable the iTunes radio option (I figured it out, they apparently changed something in the newer versions of iTunes).
As an aside, this is where the Advanced section comes in to play. The following commands will do this from the Advanced tab, one line per text field:
defaults write &homePath& /Library/Preferences/com.apple.iTunes disableRadio -bool NO
chown -R ¤t_user&: &homePath& /Library/Preferences/
Alternatively, you could leave out the second line and tell SC to fix the user's permissions from the Permissions tab. Obviously, if you download 2.6.4 there is a nice button to do it for you, but this is a good example of how SC can be programmed after the fact to do things I may not have implemented.
I have found a problem with the Advanced tab in 2.6.2 and 2.6.3 that is fixed in 2.6.4 and does not exist in versions prior to 2.6.2. If you use the Advanced tab, click on the Users, Groups or Folders tab (whichever you are in) AFTER you choose the Advanced tab and it will work fine. 2.6.4 fixes this.