domains without hostnames

[Samo]

Hi!

I'm a newbie to DNS and this is the only list I found so
don't beat me up if I ask a way too simple question. How
could I set up an MS DNS server (NT 4.0) to serve a domain
without a hostname (e.g. domain.com instead of
www.domain.com)?

Thank you for the answer!

Greetings,
Samo Gazvoda