Sounds like the display is dead. Especially if this issue is present at all times when the system is turned on.
You'll need a replacement display or a replacement laptop. You can check www.parts-people.com to see what a used display would run you for your model, assuming they have any. Compare that against the cost of a new laptop.
My Dell laptop screen has a black blob and streaks of black on it, the background is all white with a "rainbow" ribbon along the left side. I don't know if it was stepped on (the screen is not cracked) or what happened. Does anyone have any suggestions on how to get it back in working order?