at present the only item not of interest to ordinary users is 'Manage Talks'. There is a mechanism to hide/show menu items from ordinary users, but that is only items like scheduling and mass mail which will only be visible to specially authorised admins. 'Manage talks' falls in between, so I am not in favour of having a special mechanism for just one item. The server does not have all that much memory, and the less it has to do the better.
ok am ready to do this now. At present the permissions are hardcoded. We need to have the ability to add sections, which is easy and also a is_visible_to field where the admin specifies who can see/use the particular menu item. This way the admin will have total control. He ofcourse needs to create groups that have varying levels or groups of permissions. In this way, a user will only see menu items that he is allowed to access