Well depending on the type of "lines" ruining down the screen it could be something as simple as the LCD flex cable not being attached properly. Usually you get a almost plaid style or checkerboard like line pattern when this happens. So just unplug it and reseat it and see if it gets better. Otherwise it sounds like a damaged LCD. If you could provide a picture it may help. Also just to be safe check the pins on the LCD connector that is on the board make sure none look bent or missing. If you still have the first screen that didn't turn on. You can try plugging it back in and then doing a soft reset by pressing the power and home button for 10 seconds to see if it kicks it on.