NT4 registry settings to change local DNS IP

I am working on migrating an old NT4 server that was a member server in an
NT4 domain and now want to make it a file server in a 2003 domain. The
problem is that when we try to access the tcpip settings from the gui then we
get an error - System database is locked.

I found and changed the server IP settings but can't figure out where to set
the local DNS settings - this is not to mean any DNS server settings but the
local settings for the NIC card.

Until I can change the DNS settings I can't get the NT4 to be able to join
the 2003 domain.

I hope someone can shed some light for me.