there will only be one php.ini file that needs to be edited.
did you create the phpinfo.php file like i instructed in my initial reply?
create that file and view it in your browser.
look for the Loaded Configuration File section, this will tell you the php.ini file that needs to be edited.
restarting the pc will restart the server, but your server should also have a control panel where you can start and stop the apache service without having to reboot the computer.