Tickets to purchase prior to or where is best?

Hello Christine. For admission to the Villa Borghese Galleries at Rome, reserving the tickets, four weeks in advance is recommended. The Villa Borghese Galleries has beautiful white marble sculpture by Bernini.

For Florence, I would buy advanced tickets to the Accademia (museum that houses Michelangelo's David) and the Uffizi. Both generally have a long line but your advance tickets give you a certain time to show up and you get to enter right away or within 15 minutes. There is a fee for booking online in advance but its worth not waiting in line. Have you read RS Italy book? He has good tips for skipping the line at the Colosseum in Rome and San Marco Basilica in Venice.

I also think reservations for the Uffizi and Acadamia in Florence are worthwhile. We were there late October and there was a really long line of people who hadn't made reservations. You shouldn't have to make them a long time in advance, two or three days may be plenty (maybe a little longer if you're traveling during vacation months).

For the ones already mentioned (Borghese Gallery in Rome, Accademia and Uffizzi in Florence), advance reservations are a very good idea; otherwise, you'll wait in long lines (in Florence) or probably won't get in at all (the Borghese strictly limits numbers of people per day). If you want the Secret Itineraries tour of the Doges Palace in Venice, or you want to climb the leaning Tower of Pisa, these also need reservations. But most other activities in Venice and Pisa don't. Detailed instructions for how to book all of these are included in the Rick Steves Italy book, which I highly recommend you look at, for all the details of each place. More than any other book, he includes exactly the answers to your questions: "how to avoid wasting time in lines?" and "what needs a reservation, what is nice to reserve, and what can I just show up for?" Depending on when you want to go to the Vatican museums, you may want reservations. Ron in Rome's points of view on Vatican booking, and other Rome reservations, are here: http://www.roninrome.com/transportation/what-to-pre-book-in-rome For Rome, investigate the Roma Pass, but according to Ron, it's not as good a deal as it used to be. It does allow you to get to the front of the line at some attractions, which is worth something by itself. For Venice, you can save a few euros per person by buying vaporetto passes and some museum admissions in advance on http://www.veniceconnected.com/buy/calendar continued...

continued.. If you are taking trains between Rome, Florence, Venice, and/or Naples, you can save a fortune by getting Mini fares in advance. Others will have detailed directions (including the Ron in Rome site above). However, note that regional trains should not be booked in advance, as the tickets bought at the stations are the same price and have fewer restrictions. The train line between Naples and Sorrento (with Pompeii in the middle) is not part of the national rail system, is not bookable in advance, and in any event is cheap. For many of your other things, reservations are not possible or required. The Amalfi Coast bus is just a regular bus (no reservations, just buy ticket that day); but, if by "ride" you mean a private driver, you should book that in advance. For Capri, if you're doing a day trip, you want to buy round trip boat tickets when you buy your ride over, as I've read that the boats back can get sold out. Pompeii doesn't require any reservations, unless, again, you want to arrange a specific guide.