Do you have a user level table created in your database? It looks like the database you are using may not have any tables defined in it.
a common UserGroup table definition would look like this:
CREATE TABLE `usergroups` (
`UserGroupID` int(11) NOT NULL AUTO_INCREMENT,
`UserGroup` varchar(50) DEFAULT NULL,
PRIMARY KEY (`UserGroupID`)
) ENGINE=MyISAM AUTO_INCREMENT=2 DEFAULT CHARSET=latin1