Green spot on Samsung TX-R3079WH TV screen

Hi all, I'm a Nubee to technical issue threads but I'm a my witts end with this issue and need help.I purchased a Samsung TV model# TX-R3079WH and about 18 months later noticed a green blotch on the top left hand corner about 3-5 inches around and called Samsung and they sent me to a warranty station who said that he needed to demagnetize the screen.He later called me that day and said that it was fixed but it wasn't covered under warranty and chraged me $25.00 to fix which I paid.Once I got home and the television got warm it came back.I have been living with this annoying issue and my wife has been getting on my case over it.Now 10 months later I'm wondering if there's anyway I could fix this issue once and for all without  having to throw it away or smaching with a bat.My TV sits in a built in wall unit with 2 high hat lights above the unit which hardly ever get turned on and I have the cable box and my dvd player below the televison on a tv stand which I made to fit into my wall unit out of wood.Any suggestions would be greatly appreciated..Thanks in advance.CNTMDC