I run a server at home and get my Internet connection from my cable company via DHCP.
With my last router, I was able to specify my home DNS server to the DHCP server as the primary (so that the clients could navigate the house) while using the cable company's DNS addresses (received from the cable company's DHCP server) as secondary/tertiary to pass on the the DHCP clients.
Can I do this with the DSR-250? I recognize that the cable company doesn't change its DNS server addresses very often, but it does happen.