how to install graphviz

I download graphviz-2.34.zip from "Download->windows->graphviz-2.34.zip".
I am using protege->OWLviz, and i get an error "A DOT error occurred", to solve this i want to install Grahviz and set the dot.exe path to OWLviz.
But i dont know how to install Graphviz,please give step by step procedure.
Thanks.

Normally, Windows users

Normally, Windows users should use the .msi package, as this contains a standard Windows GUI for guiding the installation. The .zip package is for users who can't or don't want to use the Windows installer. That said, you can use the .zip package to install Graphviz by simply unzipping the package in the desired folder, usually C:|Program Files.

In either case, you will need to tell OWLviz where to find dot.exe. This can be done following the instructions at:

http://protegewiki.stanford.edu/wiki/OWLViz