How to use "Que Barbaro" in many ways?
Are there different ways to express that phrase (Que Barbaro) in different Spanish speaking countries?
Can you show some samples and meaning, on how you use it in your country?

Question

How to use "Que Barbaro" in many ways?
Are there different ways to express that phrase (Que Barbaro) in different Spanish speaking countries?
Can you show some samples and meaning, on how you use it in your country?

Answer

It's used that way especially in Argentina, as long as I know.

Answer

It depends on the context. Usually used to emphasize a fact or admiration for someone. 
For instance:
 ¡Que bárbaro! !batió el record mundial de los cien metros lisos!
¡Que bárbaro! !Las olas alcanzaron una altura de 20 metros a menos de una milla de la costa!

Answer

It is used to express perplexity when you see someone who is in some way (positively or negatively) exagerate or did something exagerate.

Examples:
       If you see someone that eats 5 hamburgers in his lunch time, you might say: "qué bárbaro".
       
       You may say it of someone who is extremely intelligent, brave, strong; opportunist, lazy, disorganized etc.