I have just been in a very nice B&B and I felt I had to share the experience, so I even created a place here on 43places for it:

http://www.43places.com/places/view/405042

(the official site being http://www.il-tulipano.it instead).

The place is very nice and cosy, and the people who run it are extremely nice too.
It is close to Venice, and to Padova, and to a lot of other places you should visit while in Veneto, and just in the countryside enough not to make it only a touristic “always running” holiday but also a “relaxing-in-the-nature” one ;-)