Please Help!!!1099-R tax form- How do I figure taxable income?

I received a 1099-R form on a closed pension account when I switched jobs. I am not rolling this over, just cashing out. I have an amount in Box 1, but box 2(taxable amount is blank) along with every other box except employee ID #'s. I also have no distribution code in box 7. How do I figure out the taxable amount and distrbution code?