It is the best option if the box does not need to be associated with a particular paragraph, just the page. In addition to the right-click menu, the settings also can be found in the Drawing Object Properties dialog, that appears when the border of the text box is chosen.
This sets how the text box is integrated with the characters that surround it, the paragraph it is in, and the page it is on. The Anchor, Wrap, and Arrangement can be set.
It is treated like other objects in Writer, such as images and shapes. Many times the text box is not set the way you want it.