I have inherited a network which has not been configured according to best
practice in many respects. Additionally, the previous network administrator
did not leave on good terms with the employer.  The organization is very
lean-staffed.

It's a single domain Server 2003 forest in native mode. There are no WINS
servers in the domain (which I understand is a problem). A single Exchange
2003 server is installed on a Windows 2000 member server. OWA is supported by
IIS 3.0 on the Exchange server.  When I open Exchange System Manager, many of
the management container objects are not even populated.

Questions: 1) What would you suggest would be the best plan to move forward.
I had been considering adding WINS to the network first and provision the
existing Exchange Server so that it will then support an upgrade to Server
2003 as step #2? If so, what are the pitfalls? 2) by not having WINS on the
network, exactly what functionality is sacrificed both from a mail exchange
and systems management perspective?  I ask the question because I'm not 100%
in love with installing WINS if it isn't absolutely essential.

Any guidance would be greatly appreciated.