No... It's because Google will give you links to websites to download these themes, and many people don't have a clue what to do with them.
You'll first need a program that can handle these themes, or, in my case, a patched UXtheme.dll (which you can Google for).
The UXtheme.dll patch is the better choice, allowing you to download themes (better known as MStyles) into your C:\Windows\Resources\Themes folder. This folder stores the Windows' themes, containing the Luna and Windows Classic ones. WinMatrix.com is a brilliant community for themes and wallpapers. Once you download the appropiate MStyle/theme, you just place it into the folder and open it. This will install the theme and open the Display Properties box, where you can just select the theme like you would do with any other one.
