Let's get started!
Disclaimer:
Due to the wide variety of devices available and potential variations in their firmware, the information presented below may or may not be accurate. For this same reason, OpenDNS support will generally not be able to provide device-specific assistance beyond what is provided below. If you need further assistance specific to your device, please contact either the manufacturer's support team, or your ISP if you are using leased equipment.

NOTE:
The manual for the D-Link DSL-2750B router can be found at http://www.dlink.com/-/media/Consumer_Products/DSL/DSL%202750B/Manual/DSL_2750B_Manual_US.pdf
- In your web browser address bar, type the IP address 192.168.1.1 and type in the username and password to log into the router. (see page 11)
- On the My Network tab, click LAN
- Click the Settings tab
- Scroll down to the DNS section
- In the Primary and Secondary fields, type the following IP addresses:
- 208.67.222.222
- 208.67.220.220
- Click Apply and Okay, this should reboot the router with the new settings.
Okay, what's next?
To ensure that OpenDNS is working properly for you, please flush your browser and DNS cache by using the steps below:
http://www.opendns.com/support/article/67
http://www.opendns.com/support/article/68

REMINDER:
You are more than welcome to contact support at http://support.opendns.com if you need any assistance with setting up your network with the OpenDNS resolver IP addresses. To help us gather some information about the issue, download the diagnostic tool from the URL's below, run it and copy the results link to your support message after the test completes.
Mac: http://www.opendns.com/download/mac/diagnostic
Windows: http://www.opendns.com/download/windows/diagnostic