Installation of PHP/MySQL on Windows based system is not a complex task anymore. Many different utilities are available these day to do this. I would recommend you the "WampSevrer" tool which will setup the PHP/MySQL on your system with just few clicks.
Download Link:
http://www.wampserver.com
Download the latest version of the Wampserver from the above mentioned link and install it on your system. You can install it bu just following the instruction and choosing the default options. Then from the Programs Menu, start it using the link like "Wamp Server". When you click it, you will notice that there is a new icon on your system tray. Right click on that and choose the "Put Online" option in order to activate the PHP and MySQL services. One you are done with that, that icon will turn white - thats means both the PHP and MySQL services are running now.
You can test the installation by choosing the "localhost" option again after giving a right click on the wamp server icon. If you see that page properly.. thats mean your installation is successful.
If you have any issue, please post your error here, I will try to help you out.