Terminal 7

Yes , it is possible. Wait for him/her at arrivals level where the international flights on BA are arriving at.
JFK_E

Aeroflot arrives at Terminal 1. As long as the airline is not late you have time to go and transfer to United (Terminal 7).
JFK_E

Bonjour Dominique,

Iberia vient au terminal 7. De manhattan vous devrez prendre le train E pour la station de Jamaica et puis prendre l'airtrain pour le terminal 7

JFK_E

You have just enough time to do that. Take Airtrain (the station is located across Terminal 7)on track 1 for one stop to Terminal 8.
JFK_E

You have enough time.
You clear customs and immigration at Terminal 7.
You can transfer your bags at T7, Iberia connecting flights counter or you can take them with you to T8 and check then in with AA.
JFK_E

1. The taxi stand is right across the street on the first floor(arrivals level)
2. Not the yellow cab. Those are private taxi services that a passenger self arranges( no taxi line to wait ).
3. The yellow cab drivers will be more than happy to take you there since it is a long distance for them. By the law they are not allowed to say "No" to ANY destination requested by their customer.
4. The yellow cab will run on the meter and going to NJ area is a different zone(could be very costly). On estimate will cost you on yellow cab somewhere around $150+. Most of the yellow cabs accept credit cards(you have to request one from the taxi dispatcher at the taxi stand) so no need to carry cash.

That said, I will suggest you to take a private car to your destination. Once you arrive look for self-service Ground transportation phones. There (at no cost) you can call a private car by dialing either 31 or 34. The price will be given to you prior to arranging the service. The cars arrive usually within 10-15 min .
Here are the web sites of those two car services:
http://www.dial7.com/
http://www.carmellimo.com/
You can even get a quote on you ride at their web sites.

JFK_E