Since we don't know if our plane will be late, we were thinking of waiting till we get to Zurich before we pick which train to take to Strasbourg. The prices vary a lot so we thought maybe we'd check to fares on line before going to the ticket window, to see where the better deal is. Some rail sites give you a code to get your tickets at the window, and some make you print them up, but we presumably we won't have a printer. Does any one know which system they use or if the online and ticket window price will be very different?Thanks
Ticket window prices are the standard fare. You won't get them any cheaper except with advance purchase from the rail line websites. For instance, if you purchase far enough ahead, from the Bahn, you can get Europa-Spezial tickets from Zurich to Kehl, some for only €19 pP. Kehl is right across the river from Strasbourg. Tickets from there to Strasbourg are €3,80 pP and can be purchased in Kehl or Offenburg or online. You won't have a printer with you, but you have one now. Buy the tickets before you leave; they don't get any cheaper.
But I can't buy a ticket for travel from Switz to France on a German rail site, can I?
Oh, I erred. We're going from Zurich airport to Colmar, France, not Strasbourg, hence the Kehl connection won't work.
Well, it will still work, but it probably won't be the lowest priced option. Try the Swiss Rail website, www.sbb.ch. It will display in English (if you ask nicely). Put in Zurich HB to Colmar. Then click "Search connection", not "Fare/buy". (Fare/buy is a legacy to when they used to take your routing information and email you back in a day or two with the fare.) After you click Search connection, you will get a number of routings, then pick one and select "Fare/Buy". After that it should lead you through the purchase process.