We are considering flying into Newark and taking public transportation to the Hyatt Regency Jersey City near the PATH station... is that possible? If so, what are the options? costs? etc.

Don't really know but if it's near a Path station, you could take the Airtrain to Newark Penn Station which has a PATH connection.

http://www.panynj.gov/aviation/egtsfram.htm

Note on the NJTransit website there are 2 path stations listed in Jersey City, Grove St. & Exchange Place.

http://www.nj.com/njtransit/path.html

Have you checked to see if the hotel has a shuttle service?

How much does airtrain cost.... just curious..

The airtrain from Newark Airport to Newark Penn Station costs $6.80 one way(according to the NJ Transit site).

At Newark Penn Station, you would take the World Trade Center PATH Train, which stops at Exchange Place in Jersey City. This, I believe, is the station the is right next to the Hyatt. The PATH costs $1.50 one way.

Just want to clarify that the EWR AirTrain takes you from the airport to the Newark Airport train station. You then take a NJTransit (or AMTRAK, but cost way more) train for one stop to Newark. That's where you can take the PATH. So, three trains in total.