Wanting to send my parents to Dublin over memorial day. Prefer to do business class at least one way if not both. I have the following mileage balances:

AA: 400k
United: 200k
Delta: 60k
USair: 150k
Alaska: 50k
Hawaiian: 85k

Chase UR: 400k

I would prefer JFK to EWR but would consider EWR if the options are superior.

Any help would be greatly appreciated as I am not sure if I should be looking at partners and which partner websites to use. Thank you.