Windows 2000 server and Linux Web server

Hello,
I work for a high school who in the past have had the site hosted off site.
We are running Windows 2000 as a DC named (SMRHS.org)and a Linux machine
that will be hosting the files that are currently offsite. The managed firewall team has given us an IP address utilizing NAT.
What do I need to do when I move the file off the currently hosting server to our server
as far as DNS in concerned. Additionally, at present, it is not possible to get to the
www.smrhs.org site from within the firewall as the DC is capturing the namespace. Will I require DNS on the web server when I move the site?
I want this to be a transparent change to our site visitors.