you can't, opendns is a set of servers that resolve domain names,
these servers are not on your computer, they are external, you connect to the opendns servers which connect to the web,
the only thing you can do is change the dns servers in your router and set them to your isp's dns servers,
yep - they next posters answer will remove them from your pc, but your pc connects to your router - all internet traffic has to pass through your router first, including where to find the dns servers,
set it to automatic if you want, you still have to go through the router,
its your router that connects to the internet not your pc
without any dns servers you will not be able to view web pages,
there would be a good reason why opendns is blocking the web site
you can remove them from your pc, but its your router that connects to the internet not your pc,
your pc connects to your router