Prior to my trip to Italy, I re-watched "Don't Look Now" , "The Italian Job", and "The Talented Mr Ripley" for views of Venice. After I got back, I discovered my public library had DVDs of all 18 episodes of the German TV series "Commisario Brunetti" (based on the Donna Leon novels) all filmed in and around Venice.
"Summertime" is a classic, Katherine Hepburn on vacation...
Bread and Tulips - you need to really watch as it is in Italian with subtitles. I love it.
Maybe you can find a DVD of George Clooney's wedding weekend. There was a lot of footage of boats on the grand canal!
The Tourist with Johnny Depp and Angelina Jolie is filmed in Venice...tons of shots.
I really liked the movie "A Little Romance" starring Laurence Olivier. The movie takes place in Paris, Verona, and Venice.
We love the Commisario Brunetti services---I bought all 18 episodes so we can watch them over and over. I use them to practice my German while enjoying the scenery.
Death in Venice of course
The OP referenced "Talented Mr. Ripley," while the scenes filmed in Venice were limited, I loved that movie too, for all of the Italian backdrops and to be more specific, vintage Italian backdrops.
Casanova is another good one with Heath Ledger.
Another vote for Pane e Tulipani. Sweet, beautiful funny movie. We watch it (as well as Mid-August Lunch, Pranzo di Ferragosto, set in Rome) before every trip to Italy.
I finally got all the episodes of Commissario Brunetti from my library and watched each episode twice. Absolutely wonderful for anyone planning a trip to Venice even if you don't like mysteries. I do love mysteries and had read all of the books and was grateful that the TV episodes followed the stories pretty closely - that helped a lot with trying to follow the German soundtrack (even with the English subtitles). The scenes of Venice were the best I'd seen on film because they took you to the small side canals and alleyways and all over the different neighborhoods. The filming was first rate.