Which camera is better for fast shutter speed & crystal clear picture?

The blurriness isn't really caused by the camera ... it's caused by a lack of available light and if there is little to no available light then there will be bluriness. I won;t bore you with the technical details but one of the 3 things that controls how much light the sensor gets is shutter speed. If light conditions are low then the shutter (basically a curtain covering the sensor) has to stay open longer, allowing light to hit the sensor for a longer period, allowing the sensor to absorb more light ... think of it like a sponge absorbing water. The longer you leave it under the tap, the more water it absorbs. The problem with light is that it's basically colored paint. If there is motion in the scene then the longer the sensor (let's call it a canvas now) is exposed, the more that paint is spread all over the canvas. But not only is the light moving all around but unless your camera is on a tripod, your hands/body are also moving, moving the canvas around. That is what causes blurriness. There's another type of blurriness but it's not a problem with the type of camera you are looking at. I tried going to the links you provided but they aren't working so I can;t comment on the other points you were asking about. Just know that even with a 8000$ camera, blurriness can still be a problem if there isn't any light or if the photographer doesn't have a clue about photography.

Which camera is better for fast shutter speed & crystal clear picture?

Probably the cheapest setup to do what you say you want is the Nikon D3000 and an SB400 flash.