Thanks for the information regarding passes.

I will be happier to buy the Swiss Pass beforehand so I will check out the best prices. Thanks for the suggestions of options and regarding reservations.
I am a bit of a planner so would like to purchase and book in advance.

Dukey I did look at the timetable and the trip connecting through Zurich is the same time length as a change through Thalwil.

Thanks for the Montreux idea. Any accommodation suggestions?

Chur - Lucerne:
What about this scenic itinerary?
Chur dp 7.56 via Ruinaulta Gorge - Oberalp Pass (Glacier Express itinerary)to Andermatt ar 10.22, dp 10.28 via Schoellenen Gorge to Fluelen ar 11.40, dp 12.00 by historic (more than 100 years old)Lake Lucerne steamboat (onboard restaurant) to Lucerne ar 14.47.

dp 10.28 via Schoellenen Gorge to Fluelen ar 11.40, dp 12.00 by historic>

curious is this by train? to Fluelen? or bus? - must b ea bus if from Andermatt going south or else you have to take the shuttle train down to Goschenen? A bit more explanation please and is a nice option!

Neckervd that train trip sounds great but we will be arriving in Chur at about 6.30 pm after a trip on the Bernina Express. So don't think it is an option

I think Keckervd's trip must be by bus not train and there may be very few buses each day.

The trip I suggested is all by train (except the Lake Lucerne boat's ride). Very popular, every Swiss people knows it.
Trains and boats almost every hour; last departure from Fluelen 17.00

If you start at Lake Como in the morning, you can do the whole trip, but without the boat's ride:
Vareanna dp 7.24 - Tirano ar 8.50, dp by Bernina Express 10.03 - St. Moritz ar 12.17, dp 14.02 - Reichenau 15.52/16.05 - Andermatt 18.22/1828 - Goeschenen 18.42/19.08 - Lucerne ar 20.41

Details: http://fahrplan.sbb.ch/bin/query.exe/en

The trip I suggested is all by train (except the Lake Lucerne boat's ride). Very popular, every Swiss people knows it.

OK now that you put Goschenen in I understand - you take that short connecvting railway down from Andermatt to Goschenen and then join the Gotthard main line - a very scenic route and a great suggestion to get to Lucerne from St Moritz area and if you can't get the boat from Fluelen in some seasons keep going on the train to Arth-Goldau and change there for Lucerne - also quicker than the boat - they are some direct Goschenen to Lucerne trains too I believe.