Milan to Veince to Florence, maybe Pisa, then back to Milan, what pass should 2 travelers get?

If you are looking at a pass itself, you will definately need a pass valid for any 3 days of travel within 2 months, and if you are looking at taking a day to go to Pisa and back to Florence, then the 4 days in 2 months pass will be the one you need. However, I would actually recommend that you should price out city to city tickets for the trips you are taking, and compare the ticket prices to the cost of the pass. The tickets will include the seat reservations which are mandatory on the Milan>Venice, Venice>Florence, and Florence>Milan segments. If you have the rail pass, you will pay an additional fee, typically $15 per seat, per train, for the seat reservations, which are mandatory.
Please let us know if there is anything else we can assist you with.

I did price it out and it's much cheaper, thank you. I have a follow up question. If I select 2 traveller for any particular day and time, is the fare quoted the price per traveler, or is it the total cost for the 2 passengers? Thank you.