Brian Swan has posted a new guide to his blog today to help you get started with PHP on Windows the easy way - with the help of the Windows Platform Installer (and it's compared to a manual install too).
I started working on some of the posts that I've promised, but I quickly realized I should cover the basics first. So, in this post I'll cover the requirements, options, and instructions for installing PHP and configuring Internet Information Services (IIS). [...] I suggest reading through the entire post before starting to install PHP. I will cover how to use the Web Platform Installer (WPI) and how to install PHP manually.
The guide for the Web Platform Installer is really just a series of screenshots showing the menus and the options you'll need to check to get a complete install up and running including the WinCache tool and SQL Server connectivity. The details on the manual installation aren't as detailed since there's so many options that could be set up with IIS and PHP. They rely mostly on the instructions PHP.net provides to get it working on Windows with either Apache or IIS.