Valerie,
After you make the coin background transparent, what use do you intend for it? If it’ll stay in a raster image with a different background no problem, but if you wish to put the "coin" into another document, the background will stay white (in a rectangle) and won’t in most cases stay transparent (blended perhaps to paper, but not transparent) unless it has it’s own method of accomplishing that (such as MS OFFICE programs).
Bob
Valerie,
Open your image. Layers palette. Note you have a layer that’s called background (especially if only one layer). Double click that layer in the palette and make it a simple layer. Now you can use any of the tools to either erase, mask/invert and delete. You’ll see the background as a checkerboard. This indicates it’s transparent. Give that a try.
Bob
valerie,
When you are done editing save your photo(s) where you normally would (and if using them in MS Publisher I would suggest a jpg file).
Then Publisher make a "picture box" on your page and then click on "Insert / picture / from file / "browse" to where you have the picture saved, click on it and then OK.)