I hand filled 1040NR-EZ and I got the return. I used Turbo tax in 2007 and I got my return. Though not sure which form was that. I used FreetaxUSA 2008. I didn't get any return. I have used TurboTax for 2009 and return is accepted. But I am confused now if what I've been doing is right or not or what I should be doing??

On F1/OPT you are exempt from residency for 5-years. You must file non-resident tax return Form 1040NR or 1040NR-EZ and Form 8843. Your income is not subject to FICA taxes but you must pay federal and state income taxes. On your OPT income you will get deduction based on tax treaty between the U.S. and your country. Your U.S. Tax Return: U.S. Tax Filing Requirements for Non-Residents