I'm not going to tell you why unless you explain why you'd want to do that.
It's massively rude to the user. There's almost certainly a better way of
achieving whatever it is you want to achieve.
Yes, you can use the System.Diagnostics.Process class to obtain an instance
specific to Explorer.exe (if it is running) and call the Kill() method. Note
that your process will have to have equal or higher privileges in order to
terminate it.
