If you're going to be staying in Venice and are wanting to taste the real Venice the Trattoria alla Vedova is a great choice.
Firstly though I'd like to mention that however much I love Venice (a huge amount) there is one, well actually two, aspects of the place that really irritate me.
One is the rudeness of some of the shopkeepers, hoteliers and restaurant owners and the other is the inflated prices many charge.
I don't know about you but when I visit Venice I want to eat the local dishes and I don't want to need a bank loan to do that.
If you would like to do the same then I'd suggest you head to this trattoria as soon as you start feeling those hunger pangs. It doesn't look like much, tucked down a crumbly little alleyway, but once inside the aromas wafting out of the kitchen will tempt you to stay.
You'll get all the local specialties, cooked in the traditional manner, and you'll get them at a price that is, by Venetian standards, superb value.
I know sardines and such aren't everybody's favorite but this restaurant serves one of the best versions of Sardine in Saor that I have ever tasted.
The dish is a mix of sardines, onions and raisins which sounds simple enough but you'd be surprised at how few restaurants get it right...this one does.
Octopus (polpo) is another traditional dish that they cook well as is their seafood dish baccalà mantecato con polenta. Last, but certainly not least, is the Vedova's incredibly good liver dish - fegato all Veneziana.
If you'd rather something more conventional and none of the dishes mentioned do anything for you...don't worry. They have a good selection of very conventional Italian dishes including a great vegetarian lasagna and many of the more well known pasta dishes.
One unusual point to note is they don't serve coffee which seems very weird for an Italian restaurant but they will offer you a delicious limoncello instead. I loved the limoncello but I still missed my usual espresso.
Lastly, if you'd rather not have a full meal but are looking to simply sample the great Venetian tradition of Cicchetti (tapas like snacks), with a glass of white wine know as an "ombra", then head to the bar and order away. This is one of the best places in Venice to try this wonderful tradition.