It most likely was that your cookie settings was wrong, but did you try to go to MyBB community support?
do you need a portal / home page - it appears to be not configured . ELSE point your domain to forums URL.
http://pakbestgamers.com/forums/portal.php Code (markup): it is the portal page for your myBB installation. more details
PHPBB3 is the best free forum script you will get vBulletin is abviously excellent but pricey MyBB and SMF are also good but arent much customizable and lack some essential features