Yes, my wife and I spent a week on Canandaigua Lake. We didn't end up eating out too much, but if this is a romantic NY/Finger Lake getaway, I highly suggest the Taste of NY Restaurant at the NYS Wine and Culinary Center:
http://www.nywcc.com/taste/taste_of_NY_lounge12.php We enjoyed our Sonnenberg Gardens tour, and we went to their wine tasting room and had lunch at their cafe. The lunch was ok - I remember the cold soup being particularly nice.
these places recommended to us, but didn't have time to go:
Rheinblick German Restaurant - I was told it was authentic german in a cosy setting.
Lock's Stock & Barrel - get the prime rib.
Hope that helps. When we were on the lake, we initially thought we'd hit all these roadfood places from Canadaigua to Naples to Penn Yan to Hammondsport, but I bought so many of my CNY favorites at Wegman's, I essentially forced myself to eat-in with all those groceries. So, I'm no expert on Canadaigua restaurants - BUT I do recommend the Taste of NY Restaurant. We LOVED the NYS Wine and Culinary Center.