Sure, there's no doubt you'll end up in St. Mark's Square while in Venice. And, yes, it's even more beautiful in person than it is in all the books. But if you're like us and you don't have a lot of time, there are three things you must do.
First of all, buy some food and feed the pigeons. You won't be able to help giggling as the birds swarm around you! (It's also probably the cheapest thing you'll do during your stay!)
Second, take the elevator to the top of the campanille. The view is AMAZING! You get a 360-degree view of the tiled rooftops and intricate canal system of Venice, as well as the surrounding sea and islands. It's a great place to take a breather and take it all in. It's also a great way to START your visit and exporation of Venice because it gives you a wonderful perspective of the city's layout.
Third, come back at night, when the orchestras are playing, and have some gelato. Truly, you will feel like you are in heaven. It's pure magic!
Certainly, on every vacation, you can't do everything. We chose do skip the Doge's Palace, although we did get an inside peek of beautiful St. Mark's Basilica. If you have time, go in the morning because the line won't be as long and you won't get as hot dressing appropriately. They are very strict--knees and shoulders MUST be covered or they turn you away, even if you've been standing in the long line.