Perche's answer is, like usual, to the point and it covers almost every aspect that you'd like to have covered concerning your itinerary. Let me only add that if you take a Freccia train between the big cities, the regular seats are Ok (not worse than coach in a "normal" airline) and the business class is, well, a little better than that. I usually don't travel business or higher than that. The seats on the Milano-Como train will be fine for the short trip (if you decide to go to Como, that is).