Oh wait, there might be hope for you yet.
According to this: Wapedia - Wiki: Zune Pad
"This works well unless the user is wearing gloves or anything that the touch surface cannot "read". The user cannot adjust the sensitivity and scroll speed, but can choose to turn it off and use the button as a standard directional pad instead."
There is an option in settings to turn "Touch" off. I'm currently syncing my whole library back up, but as soon as it's done I can test it out for you.