Regarding senior circuit breaker, other income: I took an IRA distribution with state & fed withholding. Is this income to be added and do I use net amount of check?

[xmasbaby0]

You are going to receive a 1099R for the money you took out of your IRA.    Those usually come in late January/early February.  You might be able to import the 1099R from the website or you might have to key it in by hand if the financial institution that handles the IRS is not on the list for importing data

To enter your retirement income, Go to  Federal> Wages and Income>Retirement Plans and Social Security>IRA  401 k) Pension Plan Withdrawals to enter your 1099R.

[Bsch4477]

The gross IRA distribution is added to your other income. You will receive a 1099-R which will tell you your distribution and tax withheld. 

[xmasbaby0]

You will enter the 1099R into your federal return and it will flow to the state return.

[AmyC]

There are many types of income that you do need to enter, disability, food assistance, etc.  Items normally entered in a tax return, like your retirement, will carry for you. You are correct that retirement income is added, the full amount, including the tax withheld.   For full details on the MA circuit breaker, see full instructions here.