Change view by using PHP if statement?

Ok I found a few items that get my closer to what I am needing. I just can't seem to get it to work. I am testing this idea with the teaser for now.

<?php
$rendered_teaser = render(node_view(node_load($nid), 'teaser'));
?>

I found that information be reading the links below. I am still not able to get it to work but close. For some reason I get errors. I think it has to do with me placing it in the node.tpl.php and the page.tpl.php template file. Instead of $nid i used node 2 for a test and that worked perfectly. The problem is I need the node I am currently on.

http://drupal.org/node/985022
http://drupal.stackexchange.com/questions/36028/getting-the-auto-summary...
http://drupal.stackexchange.com/questions/23961/print-result-of-a-node-load

And I got it working. Any comments appreciated. I placed this on the top of the page.tpl.php.

<?php 
$nid = $node->nid;
$rendered_teaser = render(node_view(node_load($nid), 'teaser'));
?>

And I placed the print rendered_teaser where I wanted the node view to be printed.

<?php 
print $rendered_teaser
?>