DNS offer and domain redicrection is different, domain redirection is direct the our yoursite.co.nr to yoursite.blogspot.com or others for better and easy remember name, DNS registration is just setting up the DNS record, domain redirecton is also consider DNS services.
That is what I also said. co.nr does not provide any DNS control panel or something, and just redirects our lengthy url to the simple co.nr as dot.tk free domain does. So in this case only co.cc is the best option among free domains which offer full control on DNS.