GRC's DNS Benchmark checks the user's current set DNS servers against over 200 other DNS server available and measure responce time and error redirection handling. This is all easily view as the software generates in real-time graphs measure times.
Once completed, the software generates two separate reports, Tabular Data and Conculsions.
Tabular Data essentially takes all the data just collected by the software and lays it all out in a per server layout. This gives the users a detailed information and score of each server.
Conclusions tab is absolutely clever in that i takes what data has just been collected and then writes up a report about its finding and gives recommendation regarding which DNS servers you should be using and how they performed. Intelligent stuff.
This software is freeware for download and works wonderfully on all versions of Windows (9x / XP / Vista / 7).
I recommend you give this software a go and see if you are getting the best internet experience.
GRC's DNS Benchmark - Home Page