I recently (2013 September) stopped working (after 5 years on H1-B) and moved from US to Canada. After my move, I had my 401k rolled over to an IRA account. I am still a resident alien for the 2013 tax year, so I am filing a 1040. There was no tax deducted on the 1042s and the exemption code shown on box 6 is 02. What should I do?

You report it on Line 16a, with NOTHING in the taxable Line 16b.