Hi Robin and Peter, and welcome to MySwissAlps!
>> Oct 22 Day trip to Lake Como
There might be information in the following earlier threads that you will find useful:
>> Do you think that's doable - too much time on trains?
You can plan all your trips with the Swiss Timetable, and decide whether the travel times suit you:
>> what type of weather to expect?
Chilly, perhaps a bit of short-term snow in places. Very cold on mountain tops. You could just as likely encounter overcast or foggy days as sunny (but cold) days. There is more information to help you on these pages:
www.myswissalps.com/ab outswitzerland/nature/ climate
>> And what type of rail pass.
There's only one foolproof way to find out, and that is to add up the cost of all trips you are likely to make by train, bus, boat and cable car, and compare the total with what it would cost using a Swiss Travel Pass, Swiss Half Fare Card etc. There is information here to assist with that task:
www.myswissalps.com/tr ain/ticketspasses/prac tical/chooserailpass
However, if you will be out and about every day on trains, buses, boats and cable cars (until you get to Basel), my first thought is that an 8-day Swiss Travel Pass would suit you, to use from 19 Oct to 26 Oct inclusive. Local transport in Basel on 27 Oct won't cost much. A point-to-point ticket for your trip to Zürich on 28 Oct would cost CHF 34 (2nd class); or if you get in early enough and can commit to a specific departure time, a Supersaver ticket would only cost CHF 17. You can find prices, and links to buy tickets, in the Swiss Timetable (link above).
You can find out about the conditions attached to Supersaver tickets here:
www.sbb.ch/en/travelca rds-and-tickets/tickets-for-switzerland/supersaver -tickets.html