Actually, you don't have to mess with root, directly. The process involves some commandline functions, but it's pretty straightforward. All functions needed to configure PHP and MySQL can be accomplished using sudo. Go to versiontracker.com, and in the OS X section, search for the MySQL and PHP installation packages. I think they are both marked as "unofficial", but they are well done, and there's a link to some pretty throrough instructions.
As far as starting httpd from the cl, you can, if it is installed correctly. I have to say that I would rather click three times then click twice, then type, however. With the MySQL package above, there's also a lib you can install to automatically start MySQL on boot, and if you start Apache from the Sharing control panel, and leave it on when you shut down, it will start up automatically when you boot.