Do not check any of the following boxes unless they are reported to you on the W-2 with the box already checked.
What is a Statutory Employee?
A Statutory Employee is an individual contractor that is treated like an employee. If this box is checked on your W-2 form, report the income here and again on a Schedule C (Profit or Loss from a Business). When completing the income portion of the Schedule C, enter the amount shown in Box 1 of the W-2 as 'Income reported to you on Form W-2 as Statutory Employee'.
For more information, please see What is a Statutory Employee and Why You're Considered to Be a Statutory Employee.
Why is Retirement Plan checked on my W-2?
Retirement Plan should be checked on your W-2 if you were an active participant in a qualifying retirement plan.
What is Third Party Pay?
Third Party Pay is generally payments made by a third party for sickness, disability pay, etc. This box is only checked if the payments were made by a third party (insurance company) and not the employer.