Hmm.. now this is something i havent heard of ever before.
Once you have set uo your httpd.conf file and made the directory htdocs as the webroot. Any Directories within the htdocs directory (Sub Folders) should parse any extension as long as its been configured within the httpd.conf file. That being PHP in your case.
Also i dont suggest using the all in one package like apachetriad2.
I used PHPTriad when i first started, and had some errors every now and again with things not working..
Although your justing starting out you may wanna configure your own webserver, there are plenty of tutorials out there.
http://robouk.mchost.com goto tutorials / php and server tutorial. If your interested in configuring it your self.