Hmmm....that is a tough call, without knowing how much it would cost to fix it. I would probably buy a new TV, as newer ones tend to be much better than the older ones, but I would hate to say just buy a new one if it would turn out to only cost you $100 to fix your old one. If you can get an estimate on the repair without spending too much money, that might be your best option. Of course, if it turns out to be such that a repair will be expensive, you will have spent your money just to find that out. Is it worth the cost of an estimate to know if it is worth fixing or not? That, I think, is the question you should answer for yourself.
Since unplugging it seemed to do something, you might want to unplug it for a couple of days, and then try it again. You may also want to reset the TV to the original factory settings (your manual should probably be able to help you do this simply), and then, if it seems to work properly, recalibrate it as you did before. If not, then find out what an estimate to repair would cost. If it would cost a small amount of money to get an estimate, then it would probably be worthwhile to do that. If it would be expensive to get an estimate, I would just buy a new TV. I personally would not want to spend more than about $50 on an estimate, but you must decide for yourself what it is worth to you to know what it would cost to fix it.
If you buy a new one, and are on a budget, I recommend looking at Toshiba. They typically cost only a little more than off brand sets, and are generally good.
