Is the router in question wired or wireless?
The DNS numbers you were given are for a DNS server, which is responsable for looking up the name of the website you visit and translating the readable name such as "www.google.com" into a number such as "192.168.254.1" which is how computers on the Internet are addressed.
When you visit a website you ask the DNS server "what is the address of this website" the DNS server responds with "this is the address of the website". However, DNS uses a protocol called "UDP" which does not check if the response sent gets through to the client (your computer). If your network is suffering from packet loss (more likely on a wireless network) then there is a chance that the reply from the DNS server will be lost causing you to see an error page.
The first thing to check is that you have a good connection to your router wather it be wired or wireless, faulty cabling can cause packet loss and so can obstructions in the path of a wireless signal.
The reason that the UDP protocol is used rather than TCP which checks to see if the cleint received the message okay is because of speed. There are billions of DNS requests every day and the UDP protocol requires about a third of the transactions that a TCP request would.