I am currently in the van riding into Florence. The drive is as beautiful as one would imagine!
More info on getting into Rome- there is a pass for ?9 that will get you in and out of Rome and will also allow metro use. Please know that with the shuttle DCL offers to the front of the port, that the walk is only 10 minutes and it is flat. Don't spend the $70 for the bus into Rome unless you are really uncertain about travelling on your own. It was really easy!