$Session variable hell

I am wanting to assign a value in a recordset to a session variable and having no luck. It seems easy enough. I have session_start at the top of the page and then later assign $_SESSION['room_number'] = $row_Recordset1['PRV_Room'] but it just does not work. No value is assigned to the session variable. I believe I am using PHP 5. Do I need to use session_register as part of this?

It seems when it rains it pours. I wanted to simply display a recordset value using the following:

EVENTID = <?php echo $row_Recordset1['PRV_Event_ID']; ?>

and although the recordset displays fine on the page, the statement just above just shows nothing after the EVENTID text; ie, EVENTID =