If you're making a flight through Zürich, have a couple hours to kill, and want to slow the trip down a bit, read on. I had five hours to burn in Zürich en route from Muscat to DC, and figured that a walk in the fresh air of Switzerland would do my cramped legs some good!
Ditch the bags
Unless you really like carrying your carry-ons around town, leave them at the left-luggage office on the ground level below Check-in Area 2. Follow the signs for "Gepäckaufbewahrung / Left Luggage." The left luggage office is down the corridor behind the Information / Service Center at the top of the escalator leading to Check-in 2. The left luggage office charges varying prices, based on the size of your bags, and the amount of time you plan to leave them there. Check the price schedule above for details.
If you have Swiss Franc cash, the other option is to rent a locker - they'll put you back 6 Francs for a medium locker or 8 Francs for a larger one, and should accomodate most average carry-ons. The luggage lockers are to the left of the Information / Service Center, and to the right of the bank of elevators.
Catch the train
Freed from your bags head down toward the train station. Look for the sign that says "Bahn / Railway". The train station is in the basement - under the Check-in 2 building. Buy a round-trip ticket to "Zürich Hauptbahnhoff" (Main train station). If you have Euros or Swiss Francs (CHF), you can use the automated ticket machine (you'll get change in CHF, no matter which currency you use).
Check the bright yellow Departures schedule board to locate the next train departing to the main train station. Look for "Zürich HBF" or "Zürich HB" on the schedules. The departure board will list the train number ("S 16", for example). You'll use this number to figure out where to catch your train. Ticket in hand, head for the train platform, one level below the ticket windows. The trip downtown will take about 10 minutes, and there should be a train every 10-15 minutes. Hop on the train and enjoy the scenery as you pass through the suburb of Oerlikon, and then continue on to Zürich proper.
Take a Hike!
After about 3/4 of a mile, you'll reach Bürkliplatz, on the northern shore Lake Zurich. When I came through in late May, the plaza was filled with fruit and vegetable stands - a great spot to grab a quick and healthy snack before heading back to the train station. For a little more variety on the return trip, cross to the East bank of the Limmat river, and walk back north along the bank to Bahnhofbrücke, where you can turn left, crossing the bridge back to the station.
Back at the station, look at the main departures board for trains leaving for Oerlikon and Flughaven Zürich. If you're trying to situate the airport on the rather confusing train maps, it's to the Northwest of town.