Just install PHP. We just did it on one of our web servers. It's running windows 2003 standard server and it's only role is a web server.
PHP installed perfectly fine and setup all the .php extentions to the executable on the server for every site. Only thing I had to do was add in index.php as a default page.
Installing MySQL on that same server today.
Although, I highly prefer a *nix box for PHP/MySQL applications.
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smd
"I can stop peeing I gots skillzthatkillz"