I am no expert, but I am a great researcher, I found this for you
IE6 doesn't hover on anything other than a's without either Javascript or the fake tables that Stu Nichols uses. So, to get the dropdowns to work you'll need either
a: the Suckerfish Javascript (and add the little classes to your CSS sheet) as seen here: http://www.htmldog.com/articles/suckerfish/dropdowns/
or
b: stick an .htc file on your server which also is Javascript but tells IE6 to hover on anything you want hovered... webpage: http://www.xs4all.nl/~peterned/csshover.html
actual file: http://www.xs4all.nl/~peterned/htc/csshover2.htc
In the drop down menu I used with the htc file, the conditional comment for IE6 had absolutely to be placed just before the closing .
I hope this helps, this project seems to be as you say a major pain in IE6.
P.S. The pngfix does not work on the other pages either because the paths to the fix are the same as on the index page