USA income and income tax filing

Hello,

I was in USA for 160 days in 2013. As i was in US company payroll i was getting my salary there. No salary was paid in India during that time.I got some bonus and other arrears on or before 31st March 2014.   I have W2 for the year 2013 and 2014. I have few queries regarding showing US income while filing income taxes.

1. While filing income taxes for the year 2013-104 (AY 2014-2015), do i need to consider both W2 (2013 and 2014)?

2. Whether Social Security Taxes, State Taxes.Medicare Taxes could be shown for tax relief or only Fedreal Tax should be considered for relief. 

3. How USD - INR conversion should be done.. 

Thanks in advance!!!