I came in us from india in may 2008 as j1 researcher. I did not pay taxes for 2008 because of treaty benefits. In may 2009 my family joined me (my wife and two children). I didn't hv any federal or state withheld for 2009 whole year. Now I decided to stay more than two year and have to file tax for 2009 but I'm confused regarding..
1. Should I pay taxes for previous two year?
2. Can I get the benefit of my wife and dependent?
3. What form should I use to file the taxes?
Suggest the best way to file taxes for 2009... Thanks in advance

REALLY do need to know your home country is, because your question is driven by what is contained in the tax treaty between your home country and the United States.