A nice inline skating route, Nidia, is along the shore of lake Zurich.
There also is an inline skating event every two weeks – the Monday Night Skate. Whenever the streets are dry on Mondays, inline skaters meet at Bürkliplatz to start their evening tour through Zurich.
We never participated, but the almost never-ending stream of people skating through the nightly town is very impressive to watch. They suggest a few inline skating routes in town on their website.

There are different good inline skating options in the region of Zurich as well. The tour around Zurich Aiport for instance is very nice. You will be skating through a natural reserve, along a small river and can stop anytime to see the planes taking off.  Rent your skates at the Airport.
Another possible route is around the Greifensee.