How can I rank my international website?

Our website is now ranking on top 5 for a no of keywords in USA.

But we have realized that we are getting the traffic from other countries too.

I have few question regarding International SEO. I want to rank my websites(http://www.xyz.com) internationally.

In webmaster, We have set the geographical target to USA.Our website is now ranking on top 5 for a no of keywords in USA.

But we have realised that we are getting the traffic from other countries too - Uk,India,Austraila, Canada , fr,de. But our keywords are not ranking on top position

for all these countries.

I have a no of questions regarding this. I am looking for a perfect solution & best practices.

1> Should I select "Unlisted" in webmaster tool to ensure that my site is not associated with any country or region. So that It rank equally for other countries.

Does it affect the current ranking of my website.

2> Should I make my website international with the use of sub directories & hreflang.

http://www.xyz.com/uk/

http://www.xyz.com/in/

http://www.xyz.com/au/

http://www.xyz.com/fr/

http://www.xyz.com/de/

After creating these version if I set the geographical target countywide ,Does it help me to rank my website in every counrty.

3>Can I use the same content in my multi regional site(english speaking countries).We will show the currency, phone -no & Address country wise in the content. Is the

duplicate content harm the ranking of my ".com domain". What are the best content strategy for a multiregional website.

4>Should I change the metatags in each version of my multiregional site(english speaking countries).