The world is a better place because of Genius people, they  display exceptional intellectual ability, 
Very true. Who is your favorite genius? I would say Albert Einstein because he had so many important discoveries.
They only problem is that they have to specialize and narrow they efforts, though there are alot of scholars around the world,  yet many geniuses have shown high achievements in only a single kind of activity.
Ok, but who do you think is an important genius? Stephen Hawking is another one on the top of my list!
I agree about Stephen Hawking, they are usually associated with talent, but many authors (for example Cesare Lombroso) systematically distinguish these terms. 
Hmm, I don't know Lombroso's work. What is the best measurement of genius? An IQ test?
exceptional achievement shows the presence of Genius nothing else.
OK, but that can be pretty subjective. I would argue anyone that changes the world in a significant way through their academic rigor qualifies as a genius.