after much investigation, it appears this plugin (double login blocker) is causing this error:

p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px 'Lucida Sans Unicode'; color: #444444}

Warning: mysql_fetch_row(): supplied argument is not a valid MySQL result resource in /home/mysite/public_html/libraries/joomla/database/database/mysql.php on line 359

p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px 'Lucida Sans Unicode'; color: #444444}

Warning: mysql_free_result(): supplied argument is not a valid MySQL result resource in /home/mysite/public_html/libraries/joomla/database/database/mysql.php on line 362

This is serious issue. I have had individuals send blind emails saying that they cant register and this is happening.  I tracked the issue to the double login plugin, it appears.