"What country do you think is the best in Asia, Europe, South & North America?"
Well, I wouldn't say what is the "best" because this is not a good term to define a country (competitiveness sucks!) But i'd tell you what i like:
From Asia i like Japan.
From Europe i stay with Ireland.
About South America, Patagonia (Argentina) looks me a good place for get lost -in a good sense:)-
I would choose Canada for North America's Country and New Orleans or New York (USA) if you had asked about cities (and whatever city who begins with the "New" word, hehe)
You have not asked about Africa and Oceania, but anyway i'll tell you: From Africa Madagascar attracts me, and Australia from Oceania (I know, this is not much original thinking)