When you assign absolute positioning to items, it is important to note that the positioning is relative to the next defined container. This container must also have absolute positioning in order for the child elements to be positioned absolutely from the 0,0 position of the parent container.
Below is the code snippet extracted from your page:
<table height="300" width="575" bordercolor="#000" border="1px" style="position:relative;">
<tr>
<td>
<img src="Images/Paddle1.JPG" style="position:absolute; top:5px; left:3px;" id="Paddle1" />
<img src="Images/Paddle2.JPG" style="position:absolute; top:5px; left:555px;" id="Paddle2" />
<img src="Images/Ball.JPG" style="position:absolute; top:120px; left:265px;" id="Ball" />
</td>
</tr>
</table>
To ensure that absolute positioning works correctly for the images in Firefox, you would need to apply absolute positioning to the table that contains them.
While using div layers is recommended for layout control, in this case, creating three columns in your table and aligning the paddles accordingly can serve as a simpler (though not ideal) solution. Regardless, transitioning to the use of div layers for layout management is considered best practice in modern web development.
For further information on positioning, refer to this resource. It highlights the nuances of the position property across different browsers, emphasizing the importance of proper coding practices over workarounds that may function only in certain browser environments like IE.