phpBB class that retrieves common tasks
edit the private vars to your settings, this was tested using PHPBB3

<?php
    class PHPBB
    {
        private $phpbb_host = "localhost";
        private $phpbb_user = "root";
        private $phpbb_pass = "password";
        private $phpbb_dbname = "PHPBB";
        private $phpbb_prefix = "phpbb_";
        protected $phpbb_mysql;
        protected $phpbb_table;
        function __construct()
        {
            $this->phpbb_mysql = mysql_connect($this->phpbb_host,$this->phpbb_user,$this->phpbb_pass) 
                or die(printf('Error connecting to Database: %s',mysql_error()));
            mysql_select_db($this->phpbb_dbname,$this->phpbb_mysql);
        }
        public function allforums()
        {
            $this->phpbb_change_table("forums");
            return $this->phpbb_fetch("select `forum_name` from `$this->phpbb_table`");
        }
        public function allusers()
        {
            $this->phpbb_change_table("users");
            return $this->phpbb_fetch("select `username` from `$this->phpbb_table");
        }
        public function close(){ return mysql_close($this->phpbb_mysql); }
        public function GetForumID($fname)
        {
            $this->phpbb_change_table("forums");
            $sql=$this->phpbb_fetch("select `forum_id` from `$this->phpbb_table` where `forum_name` = '$fname'");
            return $sql[0]['forum_id'];
        }
        public function GetForumByID($fid)
        {
            $this->phpbb_change_table("forums");
            $sql=$this->phpbb_fetch("select `forum_name` from `$this->phpbb_table` where `forum_id` = '$fid'");
            return $sql[0]['forum_name'];
        }
        public function GetLastPost()
        {
            $this->phpbb_change_table("posts");
            $sql=$this->phpbb_fetch("select `forum_last_poster_name`,`forum_name`,`forum_last_post_time`,`forum_last_post_id` FROM `phpbb_forums` order by `forum_last_post_time` + 0 desc limit 1");
            $tname=$this->phpbb_fetch("select `topic_id` from `$this->phpbb_table` where `post_id` = ".$sql[0]['forum_last_post_id']);
            $sql[0]['topic_name']=$this->GetTopicByID($tname[0]['topic_id']);
            return $sql[0];
        }
        public function GetTopicByID($tid)
        {
            $this->phpbb_change_table("topics");
            $sql=$this->phpbb_fetch("select `topic_title` from `$this->phpbb_table` where `topic_id` = '$tid'");
            return $sql[0]['topic_title'];
        }
        public function GetUserByID($uid)
        {
            $this->phpbb_change_table("users");
            $sql=$this->phpbb_fetch("select `username` from `$this->phpbb_table` where `user_id` = '$uid'");
            return $sql[0]['username'];
        }
        public function GetUserID($username)
        {
            $this->phpbb_change_table("users");
            $sql=$this->phpbb_fetch("select `user_id` from `$this->phpbb_table` where `username` = '$username'");
            return $sql[0]['user_id'];
        }
        public function phpbb_array_rem($array)
        {
            foreach($array as $a => $b)
                if(!is_numeric($a)) $result[$a]=($b)?$b:"N/A";
            return $result;
        }
        public function phpbb_change_table($newtable){$this->phpbb_table=$this->phpbb_prefix.$newtable;}
        public function phpbb_fetch($sql)
        {
            if(!is_resource($sql))
                $sql=mysql_query($sql,$this->phpbb_mysql);
            while($row=mysql_fetch_array($sql))
                $results[]=$this->phpbb_array_rem($row);
            return $results;
        }
        public function phpbb_query($query){return $this->phpbb_fetch($query);}
    }
?>