OK, Ive noticed TONS of you have those crappy stardock things, etc. Those waste RAM, and slow down the system... INSTEAD, just get:
http://fishnet.no-ip.org:81/downloads/UXTheme%20Multi-Patcher%20(Neowin%20Edition)%202.5.1.exe
Its only 460KB.
Once you run it, it patches the theme-related file in Windows that is used to determine if its a Microsoft theme, or a non-Microsoft theme. This DOES cause a Windows File Protection error when you do this, but its only the one time.
Once this is done, you can use any non-standard theme in Windows, without needing to waste tons of RAM with third party programs, its all done in Windows as if you were using a standard theme.
Enjoy!