Can you try the following link
http://75.126.68.186/private/main.cfm?tid=60213
If this brings you the front page its a problem called DNS. ( basically computers don't understand letters for domain names so we have these massive 'phone books'(Called DNS servers) who convert my.trivia.com into whatever its IP address is and then your browser does the request using its IP.
If you can't see what I've done in the link I've replaced the words with teh IP address. This will probably only get you the front page i.e. you won't be able to actually do the quiz as the link to it will still use DNS to resolve the next page.
PS, nowt to do with LAN settings!