Important Shortcut keys of Windows

Windows key : Display or hide Start menu
Windows key + B : Goto first item in System bar
Windows key + D : Show Desktop
Windows key + E : Open Explorer (My Computer)
Windows key + F : Search for files and folders
Windows key + F1 : Display Windows Help
Windows key + L : Lock the keyboard or computer
Windows key + R : Open Run dialog box
Windows key + U : Open Utility Manager
Windows key + T : Goto first item in Taskbar, use arrow keys to continue

Windows key + Arrow Down : Set window to Restored (if Minimized) or Minimized (if Restored)
Windows key + Arrow Up : Set window Maximized (if Restored)

Windows key + 1... 9 : Swith to application in position number in Taskbar

Prt Scr (Print Screen) key : Capture the image of  entire screen and copies it to the clipboard

Alt + Space + X : Maximize Window
Alt + Space + N : Minimize Window

Windows key + + : Start Zoom in with Magnifier
Windows key + - : Zoom out with Magnifier
Windows key + Esc : Exit Magnifier