Transportation options in Rome

Try Stefano's Rome Cabs. I've been using his company since 2008. E-mail them with what you need, clearly stating how many passengers and how many pieces of luggage.

Each time that I have used him, the car and driver were top notch.
http://www.romecabs.com

Most take the Leonardo Express into the Rome Termini--leaving every 1/2 hour for about 11 Euros. It's a 1/2 hr. drive. With 7 people, you probably will find it cheaper to have a shuttle service take you directly to your hotel.

Getting to the cruise port: http://goitaly.about.com/od/romeitaly/a/civitavecchia.htm

There again, you might want to get a shuttle service to haul so many people.

If Rome Cabs is unable to meet your needs, try Rome Chauffeur. We initially tried to book Rome Cabs as suggested by many on this web site, but they were booked for our date. We were trying to book from FCO airport to our apartment in Trastavere this past May. Rome Chauffeur was able to accommodate us and I was very pleased with the vehicle (Mercedes Van) and service. There were 4 adults and the price was 55 euros.

We've always been pleased with Rome Cabs. Definitely a car service and not a taxi company as we think of them. With that large a group, being tired, perhaps being jet lagged, being in an unfamiliar environment, taking the train into Rome (where you may then have to taxi to hotel) would be a real pain in the anatomy in my opinion. It is possible to take a train to the cruise port, but you still have the large group, much luggage, and not being familiar with the surroundings. Doable, but a private transfer would be a lot easier.

Are you looking to do it the most economical way or most convenient? Rarely the same.

For 7 people + cruise luggage, Frank, it'll work out the same! ;-)
Not cheap.

Thanks all for your input. We are looking for the most reliable.