rectangle on ipad home page

I am trying to help my 80 year old mother with her ipad. When I open the home page and try to slide the "slide to open" a black rectangle with a white border appears around the "slide to open" and won't allow it to work. The same happens around the date, time, and camera icon. I plugged the ipad into my macbook pro, but Itunes wants the pass code. Unfortunately, I cannot get to the keypad page to enter the passcode because of the black/white rectangles. I have also started and restarted it many times. No luck. Any suggestions would be greatly appreciated.