Prior to making a repair, check the external things first. Make sure the unit is plugged in and then test the outlet by plugging another item into it or by plugging the microwave into a separate outlet. Sometimes it is the outlet that has a problem and not the microwave.
Remove all metal from your body that could conduct an electric current. This includes jewelry and belt buckles. Unplug the power cord and wait one hour before handling the machine. This will allow the microwave to discharge and help you avoid experiencing a shock.
More than likely, if the screen is not displaying properly it is because there is a loose connection between the LCD display and the printed circuit board, or PCB. Press the cables to the board and see if the display comes on. If it does, you have a loose connection that just needs to be tightened or resecured.
Locate the connections that link the display to the PCB and run a soldering iron along these links. This should resecure the connection and repair the display by holding the links in place.