The closest you will probably get to this, unfortunately, is an applicatin called Icbar... this allows you to have icons of running programs in the taskbar, a powerful task bar dropdown, and a fully skinnable top bar, it also replaces the "x" wiith atrue close feature, and they have a number of skins for it, including Windows XP (several)
this is actguallty pretty nice, I use all of them, the dropdown, the icons, as well as nice looking standard buttons and more! This really is a nifty little application, and although it isn't on the bottom, it is the nicest taskbar I've seen.
http://icbar.ictinus.com/