To change the current network settings of your Windows or Linux system from DNS servers provided by ISP to OpenDNS :
For Windows (7/Vista/XP) :
[This example uses Windows 7].
1. Open Control Panel > Network and sharing center and click on “Change adapter settings” .
2. Right click on the network adapter active and select Properties.
3. Left click on “Internet Protocol Version 4 (TCP/IPv4) and select Properties.
4. Under the General tab, select “Use the following DNS server addresses” and enter the following OpenDNS server IP addresses :
18.104.22.168 and 22.214.171.124
5. Click Ok for the changes to take place.
[For doing the above in Windows XP type "ncpa.cpl" from Start > Run and for Vista or even Windows 7, simply type "ncpa.cpl" from search box after clicking the Windows orb and follow the steps 2 to 5 from above.]
For Linux Mint / Ubuntu :
[This example uses Linux Mint 12].
1. Open Control Center and select Network Connections.
2. Choose the active connection and hit Edit.
3. Click on IPv4 settings and enter the OpenDNS server IP addresses 126.96.36.199 and 188.8.131.52 separated by a comma in the DNS servers field. [If the ISP assigns DHCP based addresses, change the method from "Automatic (DHCP)" to "Automatic (DHCP) addresses only" for enabling the box where the DNS addresses need to be entered as shown below.] Hit Save for changes to take place.