Router returns bad dns entries on 192.18.1.* subnet

[#1]

I have a standard Technicolor TG582n wireless router but it occasionally gives out bogus network addresses when I do a hostname lookup. It is especially obvious when I run apt-get update on my Ubuntu system which searches for a group of update servers. The log of the dns lookups shows this:
May 11 09:43:26 koetsu dnsmasq[16808]: query extras.ubuntu.com from 127.0.0.1
May 11 09:43:26 koetsu dnsmasq[16808]: forwarded extras.ubuntu.com ...
ppa.launchpad.net from 127.0.0.1
May 11 09:43:26 koetsu dnsmasq[16808]: forwarded ppa.launchpad.net ...
archive.canonical.com from 127.0.0.1
May 11 09:43:26 koetsu dnsmasq[16808]: forwarded archive.canoni...
security.ubuntu.com from 127.0.0.1
May 11 09:43:26 koetsu dnsmasq[16808]: forwarded security.ubuntu....
gb.archive.ubuntu.com from 127.0.0.1
May 11 09:43:26 koetsu dnsmasq[16808]: forwarded gb.archive.ubu...






security.ubuntu.com from 127.0.0.1
May 11 09:43:31 koetsu dnsmasq[16808]: forwarded security.ubuntu....

[#2]

Most people just switch the dns to Google or OpenDNS. I don't use the supplied router due to its abysmal wifi here.

[#3]

That looks like the routers "web intercept" feature (or some such name), it can be disabled in the GUI.
That only stores names which fail to be resolved and assigns a 198.18.1.x IP address, don't know why the original lookup failed.
If you wish to change to google or opendns the following thread may help:
http://community.plus.net/forum/index.php/topic,139047.0.html

[#4]

Quote from: npr

If you wish to change to google or opendns the following thread may help: http://community.plus.net/forum/index.php/topic,139047.0.html

Thanks for that. I didn't see it as a web configuration option, so I used the CLI to change the default name servers in the router, fingers crossed.