I installed Drupal - OpenChurch installation profile. Openchurch uses panels on the front page, but I removed the panel display because I wanted to use the Fusion theme's regions (you can get the same layout without messing with panels).
But when I disable the panel, the menu disappears from the homepage and i get a "requested page not found".
The installation profile probably has the front page variable set to the panel display you deleted, just create a new page that you would like to use as the front page (usually a new node or a view), then visit mysite.com/admin/settings/site-information and update the front page path text field at the bottom of the form with the path to your newly created page.