One simple way to fix a frozen laptop is what is called a forced shut-down and then a reboot.
What this means in layman's terms is that you must hold the power button (located between the screen and the keyboard on the left hand side of the keyboard) until the computer completely shuts down. This is indicated by the power light in the power button going out. Once this is done the reboot is just as simple as pressing the power button once to start up the computer as you normally would.