One of the new features of OS X Lion was the new finder view “All My Files.” The idea behind this was that it would show all the files stored on your computer in different categories (such as Contacts, Spreadsheets, Presentations etc..)
The downside to this is that when you have a large number of files on the computer, it becomes quickly unmanageable and is something that many people have asked me how to disable.
If you wish to turn this off and disable it as the default Finder view, simply go to the Finder in the top left menu bar and select Preferences.
Under the General tab, where it says “New Finder Window shows” choose something other than All My Files (such as your home folder).
To remove it from the sidebar, then select Sidebar in the top menu and uncheck its icon to stop it ever appearing to you again!