Why am I seeing "Undefined index: und" when I'm using LANGUAGE_NONE?
if(count($node-&gt;field_override_ads) &amp;&amp; $node-&gt;field_override_ads[LANGUAGE_NONE][0]['value'] == 0)


You need to check if a value even exists before checking the value. And I'd actually write it this way:

if(count($node-&gt;field_override_ads) &amp;&amp; !$node-&gt;field_override_ads[LANGUAGE_NONE][0]['value'])