Do you want o check how Windows 8 metro styled Start screen looks ? But you may not be wanting it to install in your system right now. There is a small utility software which helps you to test Windows 8 metro styled stat screen in Windows 7 only. Bear in mind that it is just only for testing, so it may run little bit slower in your system.
Visit this website: http://download.cnet.com/WinMetro/3000-2072_4-75911749.html
Down the application “Winmetro” and install it. When you install this application, be sure not to install any third party software which includes with “Winmetro”. Below is the link which helps you to check whether there is any third party free software hidden with the main application.
After you install the software then your Windows 7 automatically changes into Windows 8 metro styled start screen. It will look something like this as shown below.