Log into your Admin page, go to Settings, Profile Fields Mgr. click add a new field, with any thing you want. I would choose drop down list, its the best option. You can then look on the site to make sure it set the way you like. If your not happy with it, simply hit the red x to delete your added entry.

PS: I would not edit anything in the exsisting drop down boxes, this may cause the features not to work correctly