Samsung blue lines - Samsung PS42P2S 42 in. Plasma Television

I will presume it is a Plasma as indicated here----lines top/bottom or left right are not easy to fix as far as knowing what to replace.

Set has a main board that communicates with the screen and directs information there--can be in one of three general areas:

1. Main Signal board (most likely)

2. Power supply as voltages are critical (less likely)

3. Display panel (the screen unit itself with a defect inside it) the last is least likely but possible.