We have a very small (5 workstation) network with one Windows Server acting as domain controller, DHCP and DNS server. All devices are connected to a standard switch which in turn is connected to a standard broadband modem.
192.168.0.50 is the IP of the DNS server.
192.168.0.1 is the IP of the modem gateway
18.104.22.168 is Google's public DNS server
Is this a good plan? Is there any point including the modem's IP in that list? I've noticed that the Windows DNS server is receiving and caching requests for public websites. Should the Google DNS server be higher up the list?