Windows key + E = This opens the explorer Explorer window.
ALT + Tab = Suppose if you open the multiple windows.Then this shortcut will help to switch from one windows to another window.
ALT, Space, X = This will Maximize the window
CTRL + Shift + Esc =This opens the Task Manager window.
Windows key + Break = switches to System properties
Windows key + F = Search window will appear
Windows key + D = Hide/Display all windows used in the system
Windows key + R = Opens the run window.
CTRL + C = copy the documents
CTRL + X = cut the documents
CTRL + V = paste the documents
Alt + Esc = Switch between running applications
Alt + letter = Select menu item by underlined letter
Ctrl + Esc = Open Program Menu
Ctrl + F4 = Close active document or group windows (does not work with some applications)
Alt + F4 = Quit active application or close current window
Alt + - = Open Control menu for active document