Any recommendation for full day tours or guided walking tours in Rome and Florence?

There are some good tours on www.enjoyrome.com
Kay

My advice - don't do it. A full day tour is too restricting. A 1/2 day tour (or even two) in Rome might be OK but don't do them in the same day. Florence is too small for a full day tour and not even necessary for a 1/2 day. The museum have walkmans that you can rent for information purposes and it is by far better to go at your own pace (and even get lost a time or two) than to go at someone else pace.

In Rome, the wonderful agency
Scala Reale offers a 2-hour orientation hike or stroll, when combined with one of their 4-hour walks. 4-hour topics include the Vatican, Roman Forum plus Colosseum, etc etc

For Rome, let me put in a good work for Daniella Hunt at Mirabilia Urbis tours (http://www.rome-tours.com/index.shtml). We used Ms. Hunt for tours of the Roman Forum and the Colosseum, and she was excellent. We had our ten-year old son with us, and Daniella made it interesting for everyone, and concentrated on things she thought we would find interesting. We had scheduled an afternoon with her, not knowing exactly how long that would be; after about three hours, our son had had enough of the hot sun and the Roman ruins, and Daniella kindly wrapped things up and sent us on our way, with advice for the rest of our stay. I couldn't have asked for a better, more appropriate tour.