Sweet program. Thanks for sharing.
I read that you shouldn't be using anything but your ISPs DNS for speed reasons because they are the "top" of the food chain so to speak if I remember right. They get to their destination fastest. Don't have the article to link though.
This tool keeps giving me different results and recommendations each time though
You might want to check that article again, and then run the namebench program linked to in this thread.
Most large ISPs have bad and slow DNS.
If you made the assumption that your ISP treated DNS the same as say OpenDNS or Dyn or one of the other big players, then yes, you'd probably have great DNS responses in under 5 hops. I've yet to find an ISP that has a clue about DNS.