No.
You have to remove AD then reinstall AD under the right name. You will loose
all user info when you remove AD.
See:
How to Rename the DNS name of a Windows 2000 Domain
You could install a NT4 BDC if you are in native mode and then rename the
domain there. This way you would keep the domain in tact but you have to
re-migrate to Windows 2000 after you have done this and since you only have
1 DC you probably don't have that many users and it would probably quicker
and easier to just remove AD and change the name when you recreate AD and
all the users.
If you're in Native mode - then no, unless you upgrade to Windows Server
2003. If you have Exhange on the network rendom.exe won't work. And you
should know that renaming a domain is not a task you should take light upon,
even if there is a tool in Windows Server 2003. http://www.microsoft.com/windows2000/downloads/tools/domainrename/
You can define new UPN suffixes in AD Domains and Trusts snap-in, but you'll
need to change your current users to use it. This way users will believe
that you've renamed your AD and in most cases that's sufficient.