SharePoint Development & Administration + InfoPath

The following is a reference to an article which explains a simple solution to hide the Global Navigation settings from the Navigation Settings page on a SharePoint site.  If you need to allow site owners to manage the navigation links on their site, but want to control the global navigation to prevent them from changing or breaking the inheritance you can modify the Navigation Settings page (  AreaNavigationSettings.aspx ) so that the Global Navigation section is not displayed on the page.

Example customised Navigation Settings page without the Global Navigation section (from the article).

The OOB AreaNavigationSettings.aspx page is customised using inline styles, and by removing the elements used to display the global navigation settings.  Once modified, the global navigation can still be managed from the top level site in the site collection.

For details, including step by step instructions on how to implement the solution, please see:
Hide SharePoint Global / Top Navigation Settings from Sites