What is the best way to travel from our hotel in Rome in the Pantheon neighborhood to Venice? And should I get reservations ahead of time? I don't have a hotel in Venice yet, but would like to choose one based on where we would be when we arrive. We're planning on staying 3 nights.
If you know your travel date, you should by tickets now on line to get the best price for nonrefundable, nonchangeable tickets. Since there are trains at least every hour, you can pick a time that is most convenient to you and the best price. There are 2 train companies, Trenitalia and Italotreno that operate high speed trains to Venice. Takes about 3 1/2 hours. Trenitalia: use Italian station names, Roma Termini, and Venezia s. Lucia.
http://www.trenitalia.com/tcom-en
https://www.italotreno.it/en
You can have your hotel arrange a taxi to get you to Termini station. You arrive at Venice Santa Lucia station. Plenty of hotels nearby, or by vaporetto.
I agree with Sam's travel suggestion. You may find this website useful for determining where to stay in Venice;
https://europeforvisitors.com/venice/articles/top-tourist-mistakes.htm
Venice is small. You can easily get to the train station from most neighborhoods.
When is your trip ? The closer you are to your travel dates , the more difficult finding a hotel will be , particularly in Venice .
My trip is not until April, 2019
Not bad , start looking for your bookings now . As the saying goes , the early bird - well , you know the rest
take the high speed train and pack a picnic...book early for the best prices