After looking for weeks trying to fix it myself. I Hired a PHP programmer from "www.scriptlance.com" to fix the one found on this forum. Set me $75 USD but it was worth it.

Here is the conversion details from my test forum.

[code:1]Importing data from phpBB2
Connecting to Database... OK
Populating Categories... OK
Populating Messages Table... OK
Populating Messages_Text Table... OK
Populating Users Table... omsakthi: 63 - NEW sakthi_yugam: 64 - NEW Thiruma: 65 - NEW Sakthi: 66 - NEW Thumby: 67 - NEW Gauthamy: 68 - NEW Amman disciple: 69 - NEW OhmSakthi: 70 - NEW suren: 71 - NEW Sutha!!: 72 - NEW sakthi_01: 73 - NEW Sangi: 74 - NEW Sakthi Mayam: 75 - NEW Adharvana Pathirakali: 76 - NEW thondan: 77 - NEW sakthiademi: 78 - NEW SakthiPraba: 79 - NEW anukaruna: 80 - NEW Sakthi.B: 81 - NEW Gurudhasan: 82 - NEW sakthivel_dv: 83 - NEW sakthiveldv: 84 - NEW rajan: 85 - NEW kkiree: 86 - NEW harish: 87 - NEW sakthisarguna: 88 - NEW sakthiom: 89 - NEW aanma: 90 - NEW toxic_forever: 91 - NEW balanarayan: 92 - NEW K. Sankarapapavinasam: 93 - NEW Rameshsx: 94 - NEW puven85: 95 - NEW Prema: 96 - NEW sakthidaasan: 97 - NEW Gayathri: 98 - NEW RaM.A.kA.Me =D: 99 - NEW neetha: 100 - NEW sakthi_oli: 101 - NEW jaya_srikanth: 102 - NEW aishkumar: 103 - NEW sakthinagaraj: 104 - NEW Rajaram: 105 - NEW dattaswami: 106 - NEW ramadurai: 107 - NEW JOTHI: 108 - NEW srigowri: 109 - NEW amir: 110 - NEW rumeskanna: 111 - NEW viji: 112 - NEW Sakthi vijaya kumar.B: 113 - NEW OK
Complete...[/code:1]

Keep in mind that both Joomla & PHPBB2 tables need to be in the Same database.
Open up the attached php file. And fill in the details. AND ENJOY

-------------Config---------------------*/

//MySQL Database host - usually 'localhost'
$host='localhost';

//MySQL Database user
$user='root';

//MySQL Database password
$pass='enter password here';

//MySQL Database name
$db='enter username here';

// Mambo database prefix
$mosConfig_dbprefix = "jos_";

// phpBB2 database prefix
$phpbb_dbprefix = "phpbb_";

/* ---------------------------------------*/