If mouse is not working, do not worry you can use the key to run the command. The keys are as follows:
Ctrl + S - This command is used to save your document files that are currently open. Always store a document file that you are using to avoid minimal losses.
Esc key - command to close the dialog box that you open or the menu you chose. It can also be used to close the currently active window in windows.
Enter key - it gives the same effect as clicking the OK button or any of the default button.
Tab key - It is used to switch from one item to the next item in the dialog box.
Alt + F4 key - This key is used to close the active window.
Windows key - Used to activate the start menu. You can use the arrow keys up and down to select an item.
Ctrl + Esc key - if you use the keyboard without the Windows key, you can use the key combination Ctrl and Esc to activate the start menu.