I cant say probally not it is usually an apache thing using mod rewrite and is
AcceptPathInfo On
AllowPathInfo On
depending on your apache setup
Correct that is correct as the title tag is not placed in a headtags file it is print in the printheader function of pp-inc.php. You would add additional tags using headtags.htm
Can't say how to do that probally you would need to modify code in someway as descriptions are only shown on one page and the headers work with categories which have different pages.