I think there's two Builtin Active Directory groups you might want to consider adding these users to based on what tasks you'd like them to perform. The groups are the Server Operators
group and the Administrators
group. Look below for more detailed information about what rights each group would afford users. I pulled from the information from this site.
Server Operators:
On domain controllers, members of this group can log on interactively, create and delete shared resources, start and stop some services, back up and restore files, format the hard disk, and shut down the computer. This group has no default members. Because this group has significant power on domain controllers, add users with caution.
Back up files and directories; Change the system time; Force shutdown from a remote system; Allow log on locally; Restore files and directories; Shut down the system.
Administrators:
Members of this group have full control of all domain controllers in the domain. By default, the Domain Admins and Enterprise Admins groups are members of the Administrators group. The Administrator account is also a default member. Because this group has full control in the domain, add users with caution.
Access this computer from the network; Adjust memory quotas for a process; Back up files and directories; Bypass traverse checking; Change the system time; Create a pagefile; Debug programs; Enable computer and user accounts to be trusted for delegation; Force a shutdown from a remote system; Increase scheduling priority; Load and unload device drivers; Allow log on locally; Manage auditing and security log; Modify firmware environment values; Profile single process; Profile system performance; Remove computer from docking station; Restore files and directories; Shut down the system; Take ownership of files or other objects.
Additional Information:
You can add a user to a group from the Windows 2003 Server by opening Active Directory Users and Computers (ADUC). The quickest way to open ADUC is by going to Start, Run, and running the command "dsa.msc". With ADUC open, browse to a users to modify, right click, select properties, go to the "Member Of" tab and choose "Add". In the window that opens, type in the name of the group you'd like to add them to and press Ok.
I hope you find the information helpful.