from microsoft
Link :
http://windows.microsoft.com/en-us/windows7/Keyboard-shortcuts Windows logo key +D Display the desktop.
Windows logo key +M Minimize all windows.
Windows logo key +E Open Computer.
Windows logo key +R Open the Run dialog box.
Windows logo key +Tab Cycle through programs on the taskbar by using Aero Flip 3-D.
Ctrl+Windows logo key +Tab Use the arrow keys to cycle through programs on the taskbar by using Aero Flip 3-D.
Ctrl+Windows logo key +B Switch to the program that displayed a message in the notification area.
Windows logo key +Spacebar Preview the desktop.
Windows logo key +Up Arrow Maximize the window.
Windows logo key +Down Arrow Minimize the window.
Windows logo key +Shift+Up Arrow Stretch the window to the top and bottom of the screen.
Ctrl+Shift+N Create a new folder
Ctrl+Period (.) Rotate a picture clockwise
Ctrl+Comma (,) Rotate a picture counter-clockwise
Alt+P Display the preview pane
Alt+Left Arrow View the previous folder
Backspace View the previous folder
Alt+Right Arrow View the next folder
Alt+Up Arrow View the parent folder
Ctrl+Mouse scroll wheel Change the size and appearance of file and folder icons
Ctrl+F Select the search box
Left Alt+Shift Switch the input language when multiple input languages are enabled
Ctrl+Shift Switch the keyboard layout when multiple keyboard layouts are enabled
Ctrl+Shift+Esc Open Task Manager
Esc Cancel the current task
F5 (or Ctrl+R) Refresh the active window
F4 Display the address bar list in Windows Explorer
F6 Cycle through screen elements in a window or on the desktop
Ctrl+Mouse scroll wheel Change the size of icons on the desktop
Alt+F4 Close the active item, or exit the active program
Ctrl+F4 `Close the active document (in programs that allow you to have multiple documents open simultaneously)
Remote Desktop:
Ctrl+Alt+Break Switch between a window and full screen.
Alt+Home Display the Start menu.
Ctrl+Alt+End Display the Windows Security dialog box.