It's better to avoid text boxes for captions because, although captions in a
text box can be seen by a Table of Figures in Word 2007, this is not true in
previous versions, so your document will not be backward-compatible. If your
picture is not wrapped, then create the caption as an ordinary text
paragraph. If you want to wrap the picture, the best approach is to insert
the picture inline, type the caption as an ordinary paragraph, and then
insert both picture and caption in a frame.
If you're already using a table for the pictures, then just type the caption
in the cell along with the picture.
--
Suzanne S. Barnhill
Microsoft MVP (Word)
Words into Type
Fairhope, Alabama USA
http://word.mvps.org