document.ready() OR window.load() with Ajax blocking page load

document.ready() OR window.load() with Ajax blocking page load

I have a webpage in Oracle Apex for which I use AJAX to load dynamic text.
 
The webpage has some flash based charts which display as soon as the page loads. These charts load xml from oracle on the fly and display chart data. 
 
After using document.ready or window.load in the head section of the page to place this text in a SPAN tag, the page seems to hang until and remains blank until all the chart data is loaded and then the whole page gets displayed.
 
I would rather have the span tag load last but have the rest of the page load with the charts than make the page apper blank/hung. What can I do to make the rest of the data load and then finally get the AJAX load to the span tag.
 
Best Regards,
Sumit.