I can’t right-click save jpg or gif

For the last month my computer will not let me right-click save as jpg or gif. This is really frustrating as it is one of my favorite things to do with my computer. If I right-click and hit save as, it opens the save window and it is labeled, untitled bmp. I can change the name if I want but it will not let me save as anything but bitmap. I have an AMD Athelon 1.2 gig with 480 megs of ram, 14 gig hard drive (half full) and I am operating with Windows ME. Someone help