Disable the automatic DNS Name Configuration

I am using Cisco Linksys WRT100 Router. I configured it as PPPOE connection through my ISP. When I am done with the tool to establish the reaction of the DNS name services, I want to configure it manually and put it as my top DNS choice. I can set up three static IPs but I was unable to locate the configuration for turning off the automatic DNS name configuration from my provider. I run the cmd then IPCONFIG /all to check all the available connections, the listing for DNS has two DNS Name Services in advance to my three static IPs which I just configured. How can I change that? Please help.
