Windows Server 2003 Standard R2 DNS

I have a Windows Server 2003 Standard R2 and it is acting as Domain Controller, DNS, Active Directory and WINS servers. I changed a websites name servers and then browsed to the address before DNS propegated. Well I apparently by doing that made a bad DNS entry on my DNS server. To be able to navigate to the site after DNS propegated, I had to restart the DNS Server services. All was good until the next day when I had to do the same thing and so on. I have cleared the DNS cache and everything else I can think of. How do i make this bad entry stop coming back? Thanks in advance.