It doesn't matter if you use Fraps. Save replay by pressing 2 in the game, then go to replay, and press pause, and do whatever you want. Take the text of with SHIFT+F. Use AA, AF, take .PNG screenshots with Fraps, or otherwise the screen will suck.
Otherwise if the screen shot is not in very good quality, most people don't want to bother to edit it.
Well i think its good as is, but if you want to learn how i do mine i can make a tut on how. Heres an example of my smoke >> http://i33.tinypic.com/9t0d41.jpg As to the blur. I think the car is blured just a tad bit to much but other wise i see no problem, nice job