How can I change the title of a survey?

Click on the General tab in the survey's view and specify a new title of the survey.

What is a public survey?

Every survey can be in draft or public state. A draft state means that the design of the given survey is not yet completed. A survey in the public state is ready for use and can be published.
A new survey is always in the draft state. Change its state in public if you finished with survey's design. To do that, click on the General tab in the survey's view and set the state property.

See also: survey items