This option can be changed in the Layout options for images within Word. To do this you need to change the text wrapping layout of the picture to either behind the text or in front of the text. This is fine if you want the picture to act like text and move around with the text in your document but if you want to move the picture around freely then this is easy to change. You may have noticed that when you insert a picture into Microsoft Word that it stays in line with the text and you can't drag it to where you want it to be.
Images placed into Word documents are usually treated like text when it comes how they are placed in the document. Microsoft word allows you to place clipart and photographs into your documents to add extra touches to your document or to help get your point across.