I was having a problem having everything work on my PCLinuxOS notebook when connecting the internet. The browser worked and I was able to hit the other machines on the network. email, Weather Widgets, RadioTray did not connect to the internet.
I changed to Open DNS settings and everything for the internet now works. Browser, Email, Weather Widgets, RadioTray, etc. Everything connects to the internet.
However, I can no longer connect to other local machines on the office network
Your office's DNS was providing the name resolution for internal machines (which cannot be provide by an external DNS such as OpenDNS, because they are not aware of the office PCs, and I doubt your office wants them to be, or that they even have public IPs).
The office DNS may also use a transparent proxy (maybe even caching , for performance), which could include limited access to some ports, which could affect apps such as email, etc...; or block specific sites.
If you have a good relationship with the IT person in your office, they may be able to help you (or, you may be cautious, if you think they may feel slighted at your attempts to circumvent their security measures...)
If you know the IPs of the PCs you connect to, you could use those. If they're static, you could even add them to you
/etc/hosts file, and use that for name resolution. If they're DHCP, and actually change, over time, then you'll be chasing a moving target...