I actually know where some of the better bead shops are in Venice. You can find them in a lot of places because Murano glass is everywhere, and that is where some of the most beautiful beads come from.
You see all kinds of beautiful necklaces and bracelets there - all glass beads. The entire city is virtually a big beautiful shopping mall (but not with the Gap or Kohls, all private stores).
I don't know about dining there unless you have a recommendation, but I would spring for a caffe latte at the Cafe Florio in St Marks Square. (Probably costs about $15, buts its supposed to be the oldest sidewalk cafe in the world - Joe Farcus has dedicated many Carnival rooms to it).