Win2K Pro trying to upgrade DNS server

We have an NT 4.0 server and a UNIX DNS server. New installs of Win2K Pro workstations seem to default to “Register this connection?s address in DNS”. Our DNS server admin. feels this is a security risk and rejects the upgrade causing increased network traffic until we disable it. It there a valid reason for this default setting or is a security risk and a feable attempt by Microsoft to fix WINS?