Create a new administrator account by creating a new user and adding them to the Administrators group and duplicating all the account policies and permissions granted to the default Administrator account. Then remove all rights and permissions from the default Administrator account.

Everything made sense up untill the last sentence.
 
Which rights and permissions do you refer to? As far as I am aware the only file/registry access rights that are assigned specifically to the 'Administrator' account by default are to the 'WINNT\Profiles\Administrator' dir, sub directories and files and to that account's profile settings in the registry. Everything else "admin-wise" is given the 'Administrators' user group. You can't delete or disable built in accounts on NT through the users console, so I'm still at a bit of a loss.

I would just rename the administrator to something that will not be easily guessed and then create a Administrator account with very little rights or permessions as possible.
 

Quote:You can't delete or disable built in accounts on NT through the users console, so I'm still at a bit of a loss.  
 

 
You are correct sir. Administrator and Guest cannot be deleted because they are built in accounts.

make the admin account name
gh40883gh7580hg75hg7g94
Make its password ¿&*(^#&@*^7g86g8g8GBYUGBU838473204078h*H*(DH*UujmniUMNIUN*I#*&)H*@H*&*^8ghbvYC!Cr6285t&*
and don't write it down.