I will be traveling to Iceland in September from Latin America and will be arriving to JFK before embarking through IcelandAir at ~8:40, the two options that I have for that day arrive either at 2:10 or a 5:46p. Do you think I will be able to connect from the later option? If not, and I have to take the earlier option, what can I do inside the airport all that time?
Even for your later connection, 2 hours 54 minutes are above the minimum connection time for that airport (appears to be 2 hours according to this source).
This means that you can book such a connection onto a single ticket. If the incoming flight is delayed and your will miss your connection, then you will be rebooked free of charge.
You didn't write, however, if you want to book the south america - JFK and JFK-Iceland flights onto different tickets. This is quite risky, as your will not be rebooked free of charge in case your incoming flight is delayed. Instead, the change fee can be quite high. Depending on your personal acceptable risk level, even the earlier connection may be risky.
Inside JFK, you can do the usual things that you can do in an airport while you wait:
- Grabbing a set at some cafe and working/web broswing
- Buying your way into an airport lounge
Some airports have additional features that may be interest (for example San Francisco has an aviation museum and has plenty of arts on display. For philadelphia, you can find a scavenger hunt on the web). I am not aware of any such features for the JFK aiport in New York, however.