There are many ways to speed up your internet access, and one of the methods shown by Google is none other than to change your DNS. If you want a faster internet experience, try out namebench. Basically what it does is it hunts down the fastest DNS servers available for your computer to use.
Namebench runs a fair and thorough benchmark using your web browser history, tcpdump output, or standardized datasets in order to provide an individualized recommendation. namebench is completely free and does not modify your system in any way. namebench runs on Mac OS X, Windows, and UNIX, and is available with a graphical user interface as well as a command-line interface.
Namebench is an open-source software by Google and it works in Windows XP, Vista, 7, Mac OS X, and Linux. With a change in DNS, my internet connection is slightly faster, this can be seen with the time taken to load my own blog. Download Namebench from official website