100% agree with Mart and Richard.

Fix your Admin issues. If the permissions were totally screwed up by someone that did not know what they were doing (not pointing fingers, but if you move forward with setting ALL USERS FULL CONTROL then you will be placed into that category of being an Incompetent Administrator) they can be repaired by an Admin by running the correct procedures to restore the system rights.


How to restore the default NTFS permissions for Windows 2000

Default NTFS Permissions in Windows 2000
 
Use NETDOM to verify TRUSTS
 
If as you say all your users are local admins then they should be able to do anything to their system. There are some minor things they can't do by default, but even those things can be altered by an Admin to be allowed - these things are stuff that relate to the SYSTEM account and typically are not needed by the Admin account.