Joe, this is quite common on many rear-projection sets and is the result of less-than-ideal CRT/mirror/screen angles in the name of chassis compactness. There is a technique known as "lens striping" that deals with this. Basically, you strategically shield the output of certain CRTs by...
Put it in 'Cinema' mode, reduce Sharpness to 10 or less, disable SVM (it's in the menus) and turn Video NR 'ON' (which actually disables edge enhancement). Then get a copy of AVIA and you're all set until you get it professionally calibrated :)