Split DNS with Windows 2008 Server

I have a DNS server that is on a DC that in the past typically stored the internal IP addresses for various hosts...  This makes sense for my domain environment.  But.. We also host various websites.  My question is in regards to the hosting / DNS resolution of websites.  So, for example..  On GoDaddy.com we'll use their DNS server and simply create A records pointing to the public IP of my web server.  I then have  NAT rule that sends all HTTP traffic to the private IP of my web server.  My internal DNS server returns this private IP address when queries are made against it...  Since only internal requests exists it works just fine.  That makes sense and is very simple.  Now...  I would like the ability to point GoDaddy to my DNS server directly and have it answer the public DNS queries.  I also need my DNS server to still answer private requests for users will be hitting these websites internally also..  As I understand I need to setup split DNS.  This would be two zones. One for private and one for public requests...  My only question is how to tell the DNS server to allocate one zone for private and one for public?