Here are the ones that my family visits regularly...
Restaurant Hiltl
http://www.hiltl.ch
Tibits in Zurich, Bern & Winterthur
http://www.tibits.ch
Bona Dea in the Zurich Main Station
http://www.bona-dea.ch/sites/index.php?id_b=53
This one will open this summer in Sihlcity...
http://www.sihlcity.ch/de/Restaurants/VEG.html
Enjoy!
http://groups.yahoo.com/group/Veggie-in-CH