How to get the actual value of a field in Views?
I'm assuming you are using Drupal 6, since you mentioned about PHP filed.

below is the code to retrieve value from a field and where ['tid_1'] is the token for a field. I think this is similar for Drupal 7 too.

&lt;?php     
$static = $this-&gt;view-&gt;display_handler-&gt;get_handlers('field');    

$b=$static['tid_1']-&gt;last_render; //$b contains the value of the field
$d=$static['tid_2']-&gt;last_render; //$d contains the value of the field   
//use your logic
 ?&gt;