Re: MS Windows 2003 Server
You shouldn't need to, Outlook gets its proxy settings from IE afaik. Other settings are individual to users and will need to be set up within their own profiles.
If you're using an external pop3 server and ISA server as your firewall you'll need to install the ISA Firewall Client otherwise Outlook won't be able to download your mail.
Other Office 2000 settings can be set by adding the Office 2000 ADM files to your group policy. They're available from here
Re: MS Windows 2003 Server
Providng the clients are 2k/XP, you can do this through group policy, adding the office 2000 adm templates to the GP and configuring it [as Norphy mentions].
Cheers
Nath
Re: MS Windows 2003 Server
Other option is to get the O2k resource kit and use the custom install wizard where you can configure outlook to automatically create the users outlook profile (profile name, username, server, etc) as well as the rest of office - this is all saved in an MST file that can then be deployed through Group Policy