Small towns in Tuscany: Car or Train

Padova, Ravenna(?), and Ferrara are not in Tuscany, but they are easily reached by train from Bologna, if you want do spend a couple of nights there. You can get to San Gimignano by bus, and to Firenze by bus or train, but a car will give you easier access (except for finding a parking space).

Many would say take the public transit. I personally prefer the car. Love driving between hill towns and like the freedom. For example on the way back from one town we stopped for dinner at another small town and got to see it. The driving isn't bad. Just don't make Florence your base can't park there. Also, make sure you have a GPS, I wouldn't leave home without it.

Car, it's perfect for the small towns. You can come and go when you want without bothering with train schedules and times. The driving in Italy was really a breeze. We never had a problem finding parking near the city center which is where you want to be. As long as you also rent the GPS, you'll be fine.

The roads south of Florence (in Tuscany) are somewhat hilly, but well paved. They're also very well marked with road signs, and we traveled without road maps even. We especially liked San Gimignano, Certaldo and Volterra.
Virtually every farm in the area has apartments and rooms as a secondary income source.
Sienna is best seen by taking a bus from Florence into their city center. The city's very congested and parking is difficult.

With the exception of San Gimignano, none of the places you mentioned are small towns and, aside from San Gimignano and Siena, they aren't in Tuscany either.
All the places you mentioned are cities, albeit not very large. Cars are not the best choice to visit cities, and all of them are well connected by public transport.

It is also more efficient to choose a base and visit nearby places from there, rather than changing hotels each time.

Ravenna, Ferrara, and Padua are close. You could visit all of them from Ferrara or Bologna.
Siena and San Gimignano are close. You could visit both while staying in Siena or Florence (if you plan to visit Florence as well)

As Roberto mentions, this post is quite confusing. Towns not spelled correctly and looks like a list of cities for the most part outside of Tuscany. Small cities but definitely ones on the tourist map and not small towns.

We rented a car for Tuscany and very glad we did, the countryside is beautiful and you really wouldn't see it otherwise. We took scenic drives between Siena and Pienza in the Crete Senesi area and also between Montalcino and Montepulciano in the Val D'Orcia area.
The Val D'Orcia is really scenic and without a car you won't see it.
I wanted to photograph the early morning fog that rolls off the valleys there so a car was the only way for me to do that.
We did drive to Siena and park there which was fairly easy but if staying in Siena you would not need a car and only use a car if you want to do countryside vista viewing for the most part.

Better than any separate GPS unit in my opinion is the free Waze app provided you have a data access on your cell phone.
It works great in Italy, separate GPS units are so 10 years ago.
I actually even prefer the Waze app on a smartphone to most car's internal navigation systems.

Thanks so much for the help. I am aware that the towns are in Tuscany, The Veneto, Emilia- Romagna...just did not think it mattered.

Kendra, clearly it matters to us geography geeks!

Seriously, though, transportation across regions can be challenging, so it helps to know what transit systems are in play when planning.

Some cities have been reassigned to regions over and over, due to war, politics, etc. (History geek as well.)

We visited the hill towns of San Gimignano & Volterra. We rented a car and are glad we did. You can run on your own time table that way and can cover more ground quicker. It also allows you to make unexpected stops like an impromptu stop at say a view of sweeping vistas or a winery;) The roads were all well kept and signed. You just have to know the towns on your route and follow the signs. GPS is very handy to have too.

another vote for car