SELECT * FROM users WHERE (type='member' or active='1') and level='2'

$table = new Users_extends_Zend_Db_Table();

$where1 = $table->getAdapter()->quoteInto('type = ?', 'member');
$where2 = $table->getAdapter()->quoteInto('active = ?', '1');
$where3 = $table->getAdapter()->quoteInto('level = ?', '2');

$rows = $table->fetchAll('(' . $where1 . ' or ' . $where2 . ') and ' . $where3);