Help translating static query to a dynamic one

What would this static db query look like as a dynamic one?
It counts the number of forum posts by users and ranks them in order of the most active.

$resource = db_query("
	SELECT users.uid AS uid, COUNT(node_users.nid) AS node_users_nid
	FROM {users} users
	LEFT JOIN {node} node_users ON users.uid = node_users.uid
	WHERE (( (users.status <> '0') AND (node_users.type IN  ('forum')) ))
	GROUP BY uid
	ORDER BY COUNT(node_users.nid) DESC
	LIMIT 3 OFFSET 0
");

Also, what's the best practice for iterating over and rendering out the results of this as a list.
This didn't seem to work?

foreach ($resource as $record) {
	$items[] = $record;
}
	
$block['content'] = theme('item_list', $items);

All input welcome.
Many thanks in advance,

Peter