This is fairly normal as LCD displays only have one native resolution usually 720p or 1080p. This means that the shows you are watching are most likely not HD and the display has to up convert the image to fit the screen and this is the "smearing" you are probably seeing.

 

so, going digital cable and its HD programming would help.
short of doing that, is there a way to set hdtv to not up-convert?
thanks for your insight

 

up conversion or scaling is necessary in order to display the image there is no way around it but it is possible that a Sat or digital Cable receiver would do a better job. Do you receive any over the air HD channels where you live? They should look very good.
One other thing to do is go into the Samsungs display settings and turn off all picture enhancements like edge enhancement, black level and noise reduction if it has them also turn down to at least 20% the sharpness setting. If your display has the ability to turn off the 120Hz or higher refresh rates do that as well.

 

right. since native resolution is 1080p, i guess it has to up-convert
non-hd video. per your recommendation, i have already turned off all picture enhancements. ln37c550 has refresh rate of 60 hz; however, i read elsewhere that higher rates are supposed to help the picture lag or smearing. but you are recommending otherwise, could you explain?

i'm surrounded by mountains so have not tried the over-the-air antenna. but i'm thinking i oughta try a cheap rabbit-ear just to see what i can pick up, especially with this smearing effect which is really irritating.

 

Many people have reported the the higher refresh rates actually make the picture look fake or un-natural but I think thats more up to the individual.