Thanx to everyone for their input. I found that I only needed to enter the code at the correct location. For others trying to enter Java for the first time, here is how I did it :
Java has 2 elements - the image and HTML. Use the Visual Editor to locate the area where you want to add your roll over image. At that area, add a marker ( I use xxxxx ). Now go to the Text Editor and find your marker. Backspace your marker and use Copy/Paste to enter the HTML code at that location. Make sure you have the image downloaded in the folder you are working in ( if you are working in a folder ).