You might wonder where the original Windows 7 themes are stored. Here are all the filepaths to the original Windows 7 themes, including archives of the original themes (in case you lost them).
The original theme files might be needed if you want to revert back to the default Windows 7 theme.
Tip: You can always revert back to the original Windows 7 theme by running the Windows System File Checker. Open a command prompt and enter sfc.exe /scannow. Also a system restore should restore the themes as well.
Original Themes: Location
There are a couple paths that you should be aware of:
C:\Windows\Resources\Themes (Aero Themes)
C:\Windows\Resources\Ease of Access Themes (Ease of Access Themes]
C:\Windows\Web\Wallpaper (Wallpaper of original Windows 7 Themes)
Here are the names of the original themes:
Download Original Windows 7 Themes + Wallpaper