I got the solution to this question.
The problem is not with the height of the div element nor the Images/CSS problem.
The problem is with another script
that is executed right after the window load completes, the script includes the DOM ready and remaining javascript function(s).
I've removed the next script that is executed after the window.load and placed after end of the body tag.
<body style="background-color: white;">
<div id='divLoading'>
<div class="loading" align="center" id="divImageLoader">
<img src="../../ItemSelectorImages/ajax-loader_bluish.gif" alt="Loading..."/> Loading
</div>
</div>
</body>
//The following second script is placed here so as to load after the body load is complete.
<script>
includes DOM Ready, and some javascript functions to be called.
</script>
Assumption: I think after the $(window).load(function () {
script is done, there should not be any other scripts further running.
Thanks to all the guys who commented.
If my assumption is wrong, please mention what the real problem that stopped the loading
image to show up.