From what I read and from what I can figure out (though I am sure I am wrong) you need to set permission for every person that registers.
That is exactly what you NOT need to do. Newly registered users are automatically added to the "Registered Users" usergroup (or "Unapproved Users", if not yet activated). Set the permissions for this group and you are done.
I suggest you read the Quick Start Guide section on Permissions
I cant get back in to see how to set it up at the moment because Firefox will not show the index in the ACP and of course IE7 keeps logging me out in admin.
I suggest you start with a fresh installation. Firefox should not make any problems.
Why is it a Global Moderator can access the Admin Control Panel ???
Is he member of a group that has admin permissions? Click on Permissions -> Administrators and it will show you all groups and users in the above lists, that have admin permissions assigned.
How do you set up a new Administrator ???
Multiple people including me already told you.
If someone can answer those questions for me I will check back in the morning and hopefully the index will be back in Firefox so I can again access the ACP to try to configure it once again.
Hoping is a not a suggested method of work in Computer Science.