I will assume you have a base system with Ubuntu 13.04 installed and updated.
1. Install Apache2.
sudo apt-get install apache2
[To verify] Direct a browser to the ip address of your server and you should see the placeholder page.
2. Install PHP5.
sudo apt-get install php5 libapache2-mod-php5
Restart Apache after PHP5 installation is completed.
sudo service apache2 restart
[To verify] Create a file named info.php with the following code.
<?php
phpinfo();
?>
Place the file in the directory /var/www/html
Display the file in a browser by going to youripaddress/info.php
You should see something similiar to the following.
3. Install MySQL5.
sudo apt-get install mysql-server mysql-client
4. MySQL support in PHP5
Too see the various PHP5 modules available.
apt-cache search php5
Pick the ones you desire and install them.
(php5-mysqlnd is the native MySQL driver)
apt-get install {module}
Restart Apache.
sudo service apache2 restart