Ok, that sounds encouraging!
If you are capable, It sounds like the convergence section of your tv has developed some ring cracks around the solder joints on the Convergence IC's and possibly the Resistors.. This is a repair any competent tv repair person should be able to complete, and would usually cost 200-300 dollars.
If you can find someone who can solder, I can give them specific instructions!
The convergence I.C.'s are what "control" the picture..These IC's operate at a very high temp, and usually only last 4-5 years.
If you remove the back of the set, you will want to look for the BIGGEST heatsink in there - it will lok like a large aluminum block with fins, on that heatsink, you will see 2 lage IC's , probably STK392-110, or STK392-120's or something to that effect...regardless - you can Remove the board they are mounted on, and using a Solder sucker, or solder wick, remove the old solder and re-solder all the connections on the I.C.'s
Once you resolder the I.C.'s, you should test all the large resistors near them.. pull one side of the resistor out of the board so you can check it out of circuit. they will usually have the value in Ohms, printed directly on the resistor, but you may have to use the resistor color code to find out what value they are....However, usually if there is any damage, the resistor will look like it has been HOT or fried. resolder the IC's and replace any bad resistors, and you should be good to go. If you need to order a resistor or two,
Hope that helps!