This tip will speed up the process of resolving DSN names. (I.e. web sites name resolution)
Open a new tab in firefox.
In the url/address bar type about:config
Click on the "I'll be careful, I promise" on the resulting screen that pops up.
In the Filter: field provided type ip
The list of configurable items is reduced to only contain entries with the ip string in them.
Look for the entry network.dns.disableIPv6
It will have a Status of default, Type of boolean and a Value of false
Double click on this entry it will change to bold
The Status will change to user set, Type will still be boolean however Value will now be True
What we have done is turn off IPv6 dns lookups
Restart Firefox and you should see an improvement in finding your web pages.