(Thanks to Hans Zappe for the tips!)

My suggestions for a nice night out at places I would go did I not have a 14 month 1 week 5 day old with questionable table manners at home:

One of my favorites; Swiss, modern, bistro style, all "bio" producers. Fun.

Very small, market-oriented cuisine, friendly.

Caduff's Wineloft
Big and noisy, maybe too many of the chi chi Zurichoise. Great wine cellar (you pick it out yourself), famous hackbraten. Bring earplugs.

Le Lyonnais
Alsatian-Parisian bistro type, great fish sauerkraut (I'm not making that up), even good with kids!

Small, a little weird (sort of Indianish/continental), but different.

Taverna Catalana
Great zarzuela and fish.

If you'd like some sushi or yakitori but don't want to mortgage your house to pay for Sala of Tokyo...

Oh yeah, the restaurant of the Hotelfachschule Belvoirpark is fun too. Go for lunch!

Use http://gastronomie.nzz.ch/books/nzzgastro/0/combo for detailed informations!

Weitere Tipps:

Vegatarische, indische Spezialitäten. Tolles Buffet. Man achte auf die wie-scharf-Zeichen! (Homepage)

Roter Kamm:
Super Güggeli. In Gockhausen (oberhalb Dübendorf). Nicht zu teuer.