If you want to know how to buy a TV, you should know why Refresh Rates that are denoted in terms of Hertz are different for various televisions. Keeping down the blur of the motion is very important and that is what refresh rate is all about. If frames are flashed more number of times, it gets translated into removal of blurs.
The televisions that are being manufactured nowadays come with a new technology and so, suitable adjustments are made in them for motion smoothing. So, blurring is considerably reduced in these televisions. Especially, those television sets operating at rates of 120 Hz or 240 Hz come with such a setting that enables judder reduction.