[bananalive]

Use plugin: register_addmember_process

PHP Code:

if ($x && $vbulletin->options['verifyemail'])
{
     $vbulletin->options['verifyemail'] = false;
     if ($vbulletin->options['moderatenewmembers'] OR $vbulletin->GPC['coppauser'])
     {
          $newusergroupid = 4;
     }
     else
     {
          $newusergroupid = 2;
     }
     $userdata->set('usergroupid', $newusergroupid);
     //do your stuff here
}