Is there a bus from FCO to Fuimicino City hotels?

A taxi will be your best bet. What hotel are you staying at? And do you mind my asking why you're planning to stay in Fiumicino?

When all else fails, ask the hotel. But for two or three miles, a taxi would be very reasonable in price.

Some hotels close to the airport have shuttles so contact your hotel and inquire. But as Frank says, a taxi would be dead cheap and the driver would handle your baggage. Even if there were a public bus, it is not likely it would stop at the door of your hotel.

Thanks to all for the help. Michael, we are staying in Fiumicino because we are turning in a rental car to FCO and then flying to Athens the next day. We are staying at Medusa B & B. It is about 2 miles from FCO with all the other airport hotels. It just seems to be hard to get from the hotels to the terminal and they want 20+ euros for a taxi one person, one way. Some hotels have shuttles, but not this one.

Change your accommodation arrangements. roninrome.com has suggestions near the airport. Year before last we stayed at Hotel Isola Sacre, shuttle to and from Fiuimicino 6 euro.

So you want to turn in a rental car at the airport the day before you depart for Athens? I agree - switch hotels to one that provides a less expensive shuttle. Here's the link to Roninrome's info on airport hotels: http://www.roninrome.com/hotels-spas/hotels-and-bbs-near-the-fco-airport

Hotel Tiber is a newish hotel on the river that offer shuttle service for around 9 Euro return (this was 2 years ago).