Glad to hear you got it working. I'm a bit surprised that applets want .class extensions. I would have expected them to run just like the java does without the .class.
As of PHP 5.5, the MySQL library has been officially deprecated. It is recommended to move to either MySQLi or PDO libraries for your mysql connectivity. See here for help choosing which interface you prefer: http://php.net/manual/en/mysqlinfo.api.choosing.php