Metro Start screen is one of the first changes that I noticed after installing Windows 8 Developer Preview. Underneath the Metro Start screen, you can see old plain Windows with taskbar, desktop and file manager. However, the start screen only shows basic information such as the time, settings, etc, but if you like, you can also easily enable the old Win 7 classic menu.
Windows 8 Start menu Toggle is a tiny (15KB) tool that lets you simply toggle between the Metro Start screen and the Classic start menu in Windows 8 Developer Preview.
Download it, right click and select ‘Run as administrator’ and choose your option. (Win 8 may require you to download and install the .Net 3.5.1 runtimes).