Saving a picture, but don't quite like the format it wants to save in? Well, here's the answer to your problem.

Open the picture up in whatever type of paint or photo editing program you use. Click "Save As". A window will open. At the bottom of that window you will see a drop down box that is listed as "Save as type". Click the arrow to the right and it will give you a list of formats to save your picture in. After choosing the format you wish to save it as, click "Save".

Simple, ne?