Best Way to visit Pompeii from Rome

Independent travel is the way to go; take the train to Naples Centrale, at Naples Centrale transfer to the Circumvesuviana local train next door, then take the Circumvesuviana to Pompeii

It is a solid two hour to two and half hour trip to Pompeii from Rome. It is long day to do it in the summer and you will have shorter daylight hours in Oct. I would roll out of Rome as early as it is convenient. Hire a guide at the entrance.

Try Through Eternity Tours. They have a tour from Rome. I didn't do that one but I did use them for the Vatican and Colosseum/Forum tours. By far the best tour group I've used anywhere in Europe. I prefer tours over doing it on my own. A good guide can bring a place to life. Pompeii can just be a pile of rubble if you dont know what to look for.

When we were there guides for hire were at the entrance. We may have been lucky he was terrific. He offered a variety of tour interests include different lengths. We settle on two hours with a general overview. And then spent another two or three retracing some of our steps and seeing areas that he had skipped. You do need a guide for best experience.

Jeanne, having done Pompeii twice in my life I don't usually recommend doing it as a day trip from Rome, although many tourists do. If still intent upon making the trip, I would forego the guided coach (bus) trips as they eat up so much time on the road. Taking a high-speed train to Naples will cut some of that, both ways, although that does involve making some of arrangements yourself: train to/from Naples, commuter train to/from Pompeii.

This tour (Pompeii Walk) has seen a lot of thumb's up, although you do need to get yourself to Pompeii independently to meet your tour.

https://www.sharedtours.com

Because of the distance/time involved, many of us will recommend a visit from Rome to the excavation at Ostia Antica instead, as it's so much closer, and saving Pompeii for a future trip which includes Naples/Sorrento/Amalfi Coast.

Pompeii was the site that made me want to visit Italy in the first place, and I've been several times. Much as I like Ostia Antica, I don't think there is any comparison.

If I were doing the trip from Rome, I'd catch the earliest possible Frecciarosso - the fast trenitalia train and then change onto the Circumvesuviana. If you catch the 7am train from Rome Termini to Naples (1h10) , change onto the 8:39 Circumvesuviana , you can be at Pompeii by 9:20
Depending how long you wish to take at the site, I'd strongly recommend getting back to Naples by mid afternoon, and try and spend a couple of hours at the national archaeological museum - many of the original artifacts from Pompeii, Herculaneum and other towns hit by the AD79 eruption are there.
Grab a pizza, get the last Freccia back at 19:30 - back in Rome by 20:40
If you book early enough, return tickets can cost less than €40