Question

I have a DIV with a transparent PNG background applied to it. Is there a way (use of JS is fine) for me to:

1. Have the transparency effect when images are enabled
2. Apply a normal solid background color to it when images are disabled

Answer 1

As I remember, if you set background-color and background-image, that would not work with transparent PNGs (over the transparency you will see background-color).
Te solution is to use a special css class:

.trans_back { background:red }
DIV#trans_png { background:url(reddot.png); position:absolute; left:-9px; }

Then make a script:

$().ready(function(){
  $('#trans_png').load(function(){
    $('.tans_back').css('background',$(this).css('background'));
  });
});

DIV#trans_png is used to check if image is loaded, you can do it in way you like, I prefer simplest without scripting.