I changed over from OPT to H1B on 1st October 2008 . My wife got an H4 approval in October but she is still in India and will be coming back in January 2009. As of now I do not qualify for the SPT but is it possible to wait till I fulfill the SPT requirement and file a joint tax returns with my wife. If so will I have to pay the excess tax as a non resident and then claim a refund once I file as resident (as I will be paying more tax as a non resident ) .

Thank you.

Yes, you can file jointly with your wife, but you will need to wait until 3 June 2008 before you can file. You will need to file Form 4868 to extend your filing deadline to 15 October 2009.

You CAN file as a non-resident, then amend, but that is NOT the recommended course of action. It is better to wait and file in June.