There currently isn't any function with which you could reset the preferences. If you want that, please get in touch with me (Carlyle Theas) directly, and I can help you with that.
Resetting the preferences won't affect your items.
However, if you changed anything in the "New Item Defaults" tab in the Preferences, any new items you add subsequently, after resetting the preferences, will have different default options set.
Conversely, if you want to clear the content of your Wardrobe (i.e., delete all your items), you can do so by clicking the "Clear Wardrobe" button in Preferences > Miscellaneous > Wardrobe Content.
Note that this will not affect the settings in your preferences.