Aer Lingus baggage allowances are figured in kilograms. Each excess bag on journeys from the USA is $100 e/w and each bag outside your allowance that weighs over 23kg and up to 32kg is $100 e/w.

In your case two of your bags fit within the allowance and two do not. The two that do not are assessed excess bag fees and overweight fees, for a total of $400. You will probably be able to get one or two of the fees waived if you're nice to the agent, bringing it down to $200-300.

Star Alliance status is no good on Aer Lingus.