For PC macro installation & usage instructions, see:
http://www.gmayor.com/installing_macro.htm.
To create the MACROBUTTON field, select the text that is to be clicked and press Ctrl-F9 to enclose it in a pair of field braces, thus {Text_to_be_clicked}. Then fill in the rest of the field code, so you end up with {MACROBUTTON ShowHide Text_to_be_clicked}. Once you've done that, press F9 to update the field.
For the picture, simply insert it anywhere into the document and make sure it's format is not set to 'in line with text'. Done.
Now, any time you double-click on the 'Text_to_be_clicked' that will toggle the image's display on/off.
As for the saving issue, you'll need to save the document as either a macro-enabled document (.docm format) or in the older .doc format.