I'm new at this- but I am getting scan lines moving slowly up my 92" screen with my sharp projector. I am hooked up with component video. It seems that the lines are more visible in darker parts of movies. There are no more than 2 evenly spaced lines moving up the screen at a time. Can anyone help?

sure sounds like your picking up AC hum. There are ground loop filters, and or isolation tranformers you can get IF thats the cause...