The short answer is no the snapping turtle is called Chelydridae follow this link for more information http://en.wikipedia.org/wiki/Chelydridae
Well it depends. If you get your turtle from the wild it might be very wild and bite people. Or you can have a turtle that was born in captivity and is very tame.
No, red-eared sliders are not illegal in England.
yes, mini red eared sliders do exist
Yes, red eared sliders eat minnows in the wild and in captivity.
never
no
no
yes they can be separated because by nature, red eared sliders are solitary creatures.
no
humans
Red-Eared Sliders are Semi-Aquatic turtles.
A Red Eared Slider can only "procreate" (have young) with another Red Eared Slider but they have been known to "mate" (have sex) with Yellow Belly Sliders. They probably wouldn't try to mate with any other kind of turtle, other than a Slider.
Sure, they do it in the wild. If you have pet red eared sliders and geese then as long as the geese don't pick on the the turtles you will be fine.