Well if your internet connection is down there is no way of verifying that the IP address is correct. Also how are you going to use the DNS or IP address? There would be nothing to use it for (except for your own personal amusement).
You can set yourself up as a DNS server, and import the domains from other locations so you have a local copy, then set yourself up as the primary DNS, and there you are.
To change / remove incorrect DNS / IP pairs you have to know the correct IP addres, so what you can do is compare against trusted sources at regular intervals and over-write any changed files.
If you had a permanent internet connection then if IPs change your DNS servers info should get updated ... but i sincerely doubt that you could convince a system to cache all DNS records locally...
What exactly are you wanting to do?