i think you need to get rid of $result
your $sql is ALREADY runnig mysql_query
if you want to keep $sql and $result, then do this:
$result="INSERT into forums (all your stuff here)";
$sql=mysql_query($result)
by the way, when you insert into table, raen't you supposed to do
insert into forum VALUES('first','second') etc? you're supposed to have the VALUES() arent you?