There are several organized tour options in Vienna for all ages and interests. Whether you just want to go for a convenient 60-minute ride on a hop-on-hop-off tour bus, or you would like to explore the city in a more active way on a bicycle, you can easily find the kind of tour that best fits your interests.
Check out this website for various organised tours that cover both walking tours and some other types, as well.
Here is another site that lists a bunch of guided tours and day trips. Options include walking tours, boat trips, hop-on-hop-off tours and others.
Guided hop-on-hop-off tours to discover the city in a convenient way.
This is another website where you can pick a tour of your liking. Bike-, boat-, bus- or walking tours, private tours and special interest tours. See what fits best your needs.
Horse-drawn carriages are a symbol for the classic, imperial face of Vienna. If you feel cheesy enough to try it yourself, then get off the subway at Stephansplatz station where the famous St. Stephen's Cathedral stands and book a ride with one of the carriages.
Don't forget to use your Vienna City Card (if you have one), because it allows you a free ride on one of the hop-on hop-off tours in the city, not to mention the other benefits.
For more details go here: https://www.viennacitycard.at/index.php?lang=EN