BTW, instead of reading a Wikipedia article on DynDNS, you should rather go to the DynDNS web site and see for yourself. It is a pretty good service. I have configured it for use on the public computers at a number of family centres.
IMHO, trying to filter out internet cruft is a huge waste of time, best done by a large service company like DynDNS. It is not something that a single person can do properly.