File "Married filing jointly" just make sure she has her SS card before you do (file an extension if necessary).
This brings up an interesting point that we had to research. A K-2 child who does not have a greencard, can you claim them as a dependent?
The answer is YES in most cases, anyone want to guess why?
There are several tests as to whether you can claim a child as a dependent.
In most cases, children for whom you provide support and a home qualify as dependent exemptions. Often, dependents do not fall into this exact description, so the IRS has designed five tests to determine whether a child or dependent can be considered an exemption.
These five requirements are:
• citizenship
• support
• gross income
• joint return
• relationship
We suggest you complete this simple process for each dependent so you do not make any costly errors on your tax return.
In order for you to claim an exemption for a dependent there are five requirements that must be met by each individual:
Citizenship
To qualify for an exemption your dependent must either be:
• a US citizen,
• a resident of the US, Canada, or Mexico for part of the year,
• a legally adopted foreign child who now resides in the US, or
• an adopted child living w/you the entire year in a foreign country.
Relationship
To qualify for an exemption your dependent must either be:
• a relative or
• a member of your household for the entire year.
Note: Relatives do not need to live in your house to qualify as a dependent exemption. Non-relatives can be claimed as dependent exemptions only if they also live in your house.
Joint Return
To qualify for an exemption your dependent can NOT:
• file a joint return with a spouse. Note: This means that a taxpayer is allowed to claim a married dependent as an exemption if all other four tests are met and the dependent uses the married filing separately status.
Gross Income
To qualify for an exemption your dependent can NOT:
• have a gross income of more than $3,300. Note There are exceptions to this rule, which are discussed below.
Support
To qualify for an exemption your dependent must:
• receive more than one-half of his/her total support from you.
You should disregard the support test in any of the following cases. If the dependent is:
• your child, and is under age 19 on Dec 31, 2006.
• your child, under 24 on Dec 31, 2006, and a full time student for at least five months during 2006. - IF YOUR CHILD IS A FULL-TIME STUDENT, BE SURE TO ENTER 12 MONTHS AS THE AMOUNT OF TIME THEY LIVED WITH YOU
• a permanently and totally disabled person and receives an income for services preformed for a tax-exempt organization.
Source of this information is
http://kb.taxslayer.com/article.php?id=193