Showing Different Code on Pages With Different Layouts

by 

function add_js_one_col_wpse_107240() {
  if (is_page()) {
    $pobj = get_queried_object();
    if(!empty(get_post_meta($pobj->ID,'one-col',true)) {
      wp_enqueue_script(/* ... */);
    } else {
       wp_enqueue_script(/* ... a different script ... */);
    }
  }
}
add_action('wp_enqueue_scripts','add_js_one_col_wpse_107240');
  1. get_queried_object will get you the page information. It will
    be a WP_Post object on a “Page”. global $post should probably
    work too, but this is cleaner.
  2. Use the WP_Post object information to check for the custom meta
    field    . enqueue scripts accordingly. You don’t say what the value
    of one-col is so I checked for any value at all.
  3. Hook the whole thing to wp_enqueue_scripts.