two different overriding node templates for the same node

I want to display a node (song content type) two distinctly different ways. Samples of both node layouts are located at http://drop.io/customnodetemplates

One way I want the song node to display is via iFrame from the front page (iframe_song_node_template.png image). The other is when the node displayed 'normally' (full_song_node_template.png image).

I know I can override the default node template layout with the node-song-tpl.php but I'm not sure how to go about displaying the node via a second custom node template.

1. How can there be two different custom node templates for the same node?
2. How can I tell drupal when to use the node-song-tpl.php and when to use the other one (if it is possible to have two)? I only want to use the node-song-tpl.php template via iframe from the front page and the other custom template file when displaying the node normally.

Thanks