Train from MXP Milan to Varenna (Lake Como)

Take Malpensa Express airport train to Milan Centrale.
Buy a ticket to take a train from Milan Centrale to Varenna Esino

It would look like this:
15:07 Malpensa Aeroporto T2 (Milan, Airport)
16:05 Milano Centrale (Milan)
RE 10354
2nd 15 min transfer time
16:20 Milano Centrale (Milan)
17:23 Varenna-Esino

19.70 euro

All trains are the same, there is no "best" or "worst". Once you arrive and get through the airport, just get the next train to Milano Centrale, and the first train from there to Varenna. Both trains are "regionalle", fixed price, no discounts for advance purchase, just buy on the day, and stamp your ticket before you board the train.

You can look up train times on the Italian Railways website: http://www.trenitalia.com/tcom-en
Malpensa Aeroporto to Milano Centrale takes 58 minutes, Milano Centrale to Varenna-Esino takes 1h03, 1 train per hour.

Also, be sure to buy your return ticket to Milan (or to where ever you are going next) in Milan. There are no tickets windows or machines at the train station in Varenna.

Also, be ready to immediately get off the train when it gets to Varenna. It only stops there for 1 minute. And of course, be sure to validate your ticket before you get on the train.

I wish people would stop the "One Minute Scare." You do need to be ready to get off when the train stops But there is warning as the train is slowing down and the other passengers head for the door. The train will stop long enough for EVERYONE to get off and EVERYONE get on. Be speedy but don't panic. There will be some pushing and shoving but it reasonably orderly.

Ah , Vareena a beautiful destination.

the train will stop long enough for EVERYONE to get off and EVERYONE get on.

not necessarily. Unfortunately the Capo who shuts the train doors is not invested with super powers. It is true that if somebody is actually stepping down or on the platform that will be seen and the Capo will wait a little, and perhaps exhibit a little frustration. But if somebody has not yet started down the stairs they will not be visible and the doors may well close on them. Also, if somebody has reached the ground and dropped off a bag, and then turns around to reach back into the train for another piece of luggage (or even worse gets back onto the train to retrieve another) the doors may very well close.

Put yourself in the place of the person perhaps several cars away who has to decide if those going ashore have gone and those going aboard have done that. They can't tell if somebody who just hopped on had already got off or was one of those waiting to get on.

So don't dawdle and don't go back on. Travel light.

How about phrasing it:
The train will not start if people are still getting on and off.
If you are @#§&-ing around inside the train getting your luggage, and everybody else has got off or on, the train may start.

Obviously, if it is not obvious that you are getting on or off then the doors will close. But the point is, if you are ready to get, luggage in hand, you will have ample time to step down three steps and get off. My experience is that we have never had a problem with enough time either to get on or off.

There are no tickets windows or machines at the train station in Varenna.

There is a travel agency inside Varenna station selling all kind of tickets and a tobacconist shop on the main street selling only regionale tickets. Even if regionale tickets are day specific, you don't have to get them on the day of travel.

When we were there, the station at varenna was locked up tight. Also, be advised the restrooms at the milan station are down a set of stairs and what seems like 2 blocks away, and you must have a euro coin to enter the turnstile

So, let me add to the paranoia and ask for reassurance.
I read somewhere that all of the doors might not open. Will it be easy to tell how to get the door to open if someone who knows what they are doing isn't getting off before me?
..a button to push....a handle to twist....?
Thanks!

Opening train doors
Depends on the model of train. It may be a handle, it may be a lever. The levers sometimes need a bit of brute force.
You cannot open the door until the train stops and the driver presses a button - safety measure. He may be 1-2 seconds late pressing his button, so try again.
Same if getting on a train, button or handle to pull and slide.
It is only on métro trains that all the doors open automatically.

If you have somebody else in front of you, no problem. If you have somebody behind you and you are a little slow opening the door, expect an arm to reach over your shoulder to open the door, and the person behind tutting about tourists.
You will soon learn.

Video of an Italian train, you can see the green button which opens the door: https://www.videoblocks.com/video/internal-blue-doors-of-an-italian-train-eibrehb5eikdps884

Thanks Chris!!