If you're ever in Zürich, here are some good places to eat:
An absolute must for lunch or a snack is the most famous bratwurst in Zürich (and possibly the best bratwurst on the planet) at a sidewalk grill at the Bellevue plaza. Bellevue is right at the mouth of the Limmat river (the main river in the city) as it meets the lake of Zürich (half the trams in the city stop at Bellevue, so its easy to find). The bratwurst stand is directly across the street from the Tram 15 & 4 stop. They also have good servelat (kind of a fat hot dog) and roasted chicken, and a few outside tables to sit at.
Another must is the Back 'n Brau, a local micro-brewery. There are two in Zürich, one a few blocks behind the main train station (Hauptbahnhof or HB) and the other on Universitestrasse (about 5 blocks north of the University, it turns into Winterthurstrasses). You can call or ask for exact directions depending upon where you are staying. You have to try the house brew with their fresh pretzels or bagels. They have several good baked dishes with either meat or seafood inside. The sausages and salads are also excellent. And save room for a waffle for dessert. You can also go here for Sunday brunch.
For a good local meal in a small restaurant (that you won't find any tourists at), go about 10 minutes down the east side of the lake from the city to the town Küsnact. The Weinberg restaurant is very small but has some real good local food and quaint atmosphere. I suggest you call as they only have about 7 tables, 910-0956. It is located on the bus 912/916 run (not right on the lake, about 1/4 mile up the hill parallel to the lake) on the corner just one block north of the main cross street that goes down to the bahnhof (train station). Or just go uphill from the Küsnact train station about 3 blocks and you'll find it. However, their lease was running out in 1998 so they may have moved, ask around and someone in Küsnact will probably know where.
There is a very good German restaurant in the middle of the city named Zughaus Keller. It is an old weapons depot with large tables and a bit noisy and popular with the tourists (but a good beer hall atmosphere). They have a very long menu of German sausages and special meats. It is on the Bahnhofstrasse (which starts at the main train station, HB, and goes to the lake) at Paradeplatz (3rd tram stop).
In summer it is nice to go to the Bavarian island and sit outside right on the Limmat river for a casual dinner and music. It is a self serve, but they have some good roasted chicken and the standards (bratwurst, servelat, chicken kabobs, salads). It is located right on the Limmat river just before it feeds into the lake. The closest tram stop is Burkliplatz, you'll see it from there.
Another nice place is Club 61 right on the lake (about 5 minutes from the city on the west side of the lake). You can sit outside (a slightly smaller more casual menu) or sit inside (slightly more formal and a better menu). The inside menu offers many excellent meals, you can't miss.
If you are around the Zürich Oerlikon area, the Eisenbahn is a local hole in the wall. It is very smoky and no one speaks English, but good and cheap food. Don't bother with the menu, just pick one of the daily specials written above the counter. It is located at the Oerlikon bahnhof facing track 6, on the corner. After dinner order a Baba, trust me.