latency can be caused by many things including the most likely cause which would either a local firewall/AV scanner checking every packet or a bad cable or port on the network causing mini broadcast storms.
What latency are we talking about? 90m/s? 300 m/s?
Also try using comodo's DNS servers. I'm currently using them so I know they work. If these still fail I would stick the ISP's default settings.
Almost forgot. The biggest cause of latency is other people on the network. Make sure you are the only one on th network and that your PC is the only device active and see if you still get the issues.