Research and Development
If you like Front Row and are disappointed in Lion leaving it behind, you can easily get it working again just by copying a couple files over from the prior OS version.
This will require access to a Mac OS X 10.6 installation. The following Front Row files from OS X 10.6 Snow Leopard must be moved into the exact same locations in Mac OS X 10.7 Lion:
/System/Library/CoreServices/Front Row.app
/System/Library/PrivateFrameworks/BackRow.framework
/System/Library/PrivateFrameworks/iPhotoAccess.framework
/System/Library/LaunchAgents/com.apple.RemoteUI.plist
/Applications/Front Row.app
If you have Snow Leopard installed and laying around, you can preserve and move these files yourself quickly with Finder or by using cp, just be sure to place them in the exact same locations. This is very easy if you have a dual 10.6 and 10.7 boot config going, but if not don't worry there's a simple alternative.
Alternatively to moving the files yourself, you can use use a free package installer that contains the 10.6 Front Row files and places them automatically into the appropriate locations in Lion.
Download the free package installer
However, since the update to iTunes v10.4, Apple has changed how the library is read/written (iTunesAccess.framework). As such, your iTunes Library content will not play in Front Row. A workaround: Under Users in MacHD access your iTunes folder. Make an Alias of your Movies. Drag the Movies alias into your general Movies folder.