Do you know what settings yout TV is capable of? I have a Samsung plasma and while I could get the full 1080p I kept getting bad static on the picture (same issue with PS3 and XBOX 360).
After some research I found out that this is a common problem with this model plasma screen and required a new motherboard installed. This was free of charge as it was a known problem with the TV by Samsung (This did not stop the need for an argument over the issue, but eventually the nice people at Samsung saw it my way
Anyway now it works perfectly. If your TV can do 1080p, don't settle for 720p.
For the record mine is a Samsung PS50Q91FDX