Help with timing event

[toolmanwill]

Hello, I have been adapting this code for a ratio wait time for a vbulletin torrent tracker. The problem i may be having is its not correctly getting current time and subtracting the time in an added started column which uses datetime.

here is code

//ratio wait code

$xaw = mysql_query("SELECT uploaded, downloaded FROM user WHERE MD5(password)='$passkey'") or err("VBTT v2.1.7: ".mysql_error());
while($sat = mysql_fetch_array($xaw)) 
$ratio = number_format($sat["uploaded"] / $sat["downloaded"], 2);
$yaw = mysql_query("SELECT started FROM peers WHERE passkey='$passkey'");
while($zaw = mysql_fetch_array($yaw))
 $elapsed = floor((get_date_time() - $zaw["started"]) / 3600);
 $RATIOA = .25;
 $RATIOB = .50;
 $RATIOC = .75;
 $WAITA = 18;
 $WAITB = 12;
 $WAITC = 6;
 
if ($ratio < $RATIOA) $wait = $WAITA;
 elseif ($ratio < $RATIOB) $wait = $WAITB;
 elseif ($ratio < $RATIOC) $wait = $WAITC;
else $wait = 0;

if ($elapsed < $wait)
		err("VBTT v2.1.7: Not authorized, RATIO TOO LOW (" . ($wait - $elapsed) . "hours) - READ THE FAQS!");
		

//end ratio wait code

What i'm looking at is the $elapsed string. I need it to get current time and subtract it from the started field value.
"started"field is saved in this format : `started` datetime NOT NULL default '0000-00-00 00:00:00',

Thanx in advance to anyone who can solve this for me. By the way this is for vbulletin 3.0.13 if it matters.

Will V.

After playing all day, I added a field lookup so now what i really need is a way to do this line

 $elapsed = floor(($zaw["last_action"] - $zaw["started"]) / 3600);

What it does is grabs the 2 datelines and subtracts them to get the difference, what i need to happen is to convert the dateline difference results to a numerical value in a 12.75 h (12 hours 45 minutes) type format.