I'm on F1 (non-resident alien) and spouse is resident alien. First time, we are making election to be treated as resident for tax year 2007.

1) do I need to pay back FICA (social secuity & medicare taxes) that were not withheld on my summer income in 2007?

2) since we need to attach a declaration/statement for electing to be treated as resident alien, is there any software or professionals handling addition of this document in e-filing?

3) can I file federal taxes now and state taxes in few days later? Can I use different tax prepration services for federal v/s state?

1) No; see link below:

Nonresident Spouse Treated as a Resident

2) Negative; the statement requires that you MAIL the tax return.

3) Sure; no problem.