The top screen of my ds lite has lines when I move it. how do I fix it

(I know how to take it apart)? I think it's the ribbon cable because the hinge is also cracked. I'm pretty sure the screen will sooner or later turn all white (that's what happened to my last ds). I don't want to take it in shop because I'm getting the 3ds but I still want to try to fix it. how?
 
Top