Hello,
My son's wife arrived in US in June on k-1 visa. They married and once she got her green card, she started a small business. In her native country she worked from Jan to April and had taxes withheld.
What's the best way for them to do their taxes? Should she file as resident alien? If they file married jointly, what forms would be required?
Thank you for your help.

If your son is U.S. citizen or resident, they can file joint return as residents. Both must report worldwide income for 2009. If you paid taxes in the foreign country, you will claim credit for taxes paid in the foreign country by filing Form 1116 or can file form 2555 Foreign Earned Income Exclusion. Your U.S. Tax Return: U.S. Citizen or Resident with Foreign Income

Thank you MukatA. My son is US citizen. Form 1116 is to get foreign tax credit, so they should use that, but are they eligible to also file 2555 ? His wife (resident alien) has always worked (until her move to US) in her native country.