Glad you got it figured out, but if you need anything else, just let us know! This is a common problem with Joomla modules when you set them to show on 'all menu items', because in reality, they show on all pages. To not show on pages that don't have menu items, you need to set the module to display on selected menu items and then select all the menu items.
Alternatively, you can do what you did, which makes it easier as you add new menu items (you don't have to update all your modules to add the new menu item).
Hope that helps, and good luck!
Alex
Hiding modules on registration page
