Both OAPs, my wife and I intend to take a post school holiday to the Italian lakes. We would fly into/out of Milan Malpensa and intend 4 days Stresa - 3 days Lugano - 3 days Bellagio. We are able to travel by train or boat (not bus), and currently are having difficulty in accessing travel between Stresa (or Laveno) via Guibiasco to Lugano. We have learned of travel Lugano to Bellagio (Boat to Porlezza - ? to Menagio - boat to Bellagio) and subsequently Bellagio - Malpenssa (boat to Como - train Saronno - Busto Arsizio)
During our 3 days in Lugano we hope to visit Mont Genoroso, is the Lugano 3 day regional pass worthwhile?

Have you thought about going directly from Malpensa to Lugano? It is a 60 minute direct bus -- unless you are adamant about not taking a bus (but you will probably need one to go to Stresa efficiently).

Whatever you do, I would put either Stresa or Lugano last so that you have a cheap/easy trip back to Malpensa.

What are "OAPs"-- ?

It's UK speak for Old Age Pensioner.

Can't you board a modern bus, not even a citybus? That would make things much easier.

Malpensa (MXP) to Stresa by train:
MXP T1 dp 11.50 and then every 2 hrs by Luino bound train up to Gallarate where you change to a Domodossola bound train. Journey time: 1 hr 25 min.

Stresa - Lugano all by train:
Stresa dp 8.40 - Lugano ar 11.32, change at Milano C
Stresa dp 9.40 - Lugano ar 13.32, change at Milano C
Stresa dp 13.22 - Lugano ar 16.32, change at Milano C
Stresa dp 15.40 - Lugano ar 18.17, change at Milano C
Stresa dp 16.40 - Lugano ar 19.25, change at Milano C
Stresa dp 17.22 - Lugano ar 20.25, change at Milano C
Stresa dp 19.22 - Lugano ar 22.48, change at Gallarate and Bellinzona

Stresa - Lugano by boat/catamaran and train:
Stresa dp 10.00 - catamaran - Locarno 11.30/12.04 - train - Lugano ar 13.03, change at Giubiasco
Stresa dp 11.15 - boat - Locarno 14.30/15.04 - train - Lugano ar 16.03, change at Giubisaco
Stresa dp 15.30 - boat - Locarno 18.45/19.04 - train - Lugano ar 20.03, change at Giubiasco

Trains from Laveno M to Cadenazzo every 2 hrs from 15.01 until 21.01 (only buses before 3pm) - Lugano ar 1 3/4 hrs later.
Shuttle car ferries between Intra and Laveno.
Boats from Stresa to Intra: 12.30, 14.00, 15.00, 16.00, 17.00, 18.00 (1 hr journey).

Lugano - Bellagio by train and boat:
via Milano Centrale - Varenna
or via Como SG/Como Lago

Distances boat's pier - train station:
Locarno: 300 metres
Laveno Mombello: 1000 metres
Luino: 900 metres
Como SG: 1000 metres
Varenna: 500 metres

Bus lines:
Intra - Brissago - Locarno
Luino - Ponte Tresa
Lugano - Cassarate - Porlezza - Menaggio
Chiasso railway station - Como Lago
Como SG - Bellagio

Railway lines:
Laveno Nord (boat's pier) - Saronno
Malpensa Terminal 1 - Saronno - Milano PG - Milano C
Malpensa Terminal 1 - Gallarate - Laveno - Luino - Cadenazzo
Saronno - Como Lago
Milano - Gallarate - Stresa - Domodossola, Domodossola - Locarno
Locarno - Cadenazzo - Giubiasco - Bellinzona
Bellinzona - Giubiasco - Lugano - Chiasso - Como SG - Monza - Milan
Como SG - Lecco
Milan - Monza - Lecco - Varenna
Lugano - Ponte Tresa

Generoso railway: closed in 2015 because of works along the line and at restaurant Monte Generoso
Alternatives (except buses):
Stresa - Mottarone
Locarno - Cardada - Cimetta
Rivera railway station - Alpe Foppa
Lugano - Monte San Salvatore
Lugano - Monte Bre
Como - Brunate

Thank you for your responses particularly neckervd for your extensive information which I have printed out and will study at length.
Sandralist - I am badly affected by motion sickness, can cope with smooth steady journeys but not jerky jolting as with a bus (or even family car!)
I am beginning to construct an itinery, with the only bus I think between Porlezza and Menagio.
Thanks again