I am trying to optimize a page in the following way:

The page is written using Java/JSP and the spring framework.
It includes:

HTML Code:
<div id="formDiv">

<div id="reportDiv">
When a user selects values from the form and submits it, the whole page is refreshed and a report shows up in the reportDiv.

The problem with this is, that when the data to populate the report is large, the page refresh takes a long time, and in some browsers I am seeing a blank white page for a long time until the report is refreshed.

I would like to avoid that - in other words, while the report section is refreshing, the form section should stay in place.

Two ways I was thinking of implementing this are:
1. have the report section display in an <iframe> pointing to a different JSP.
2. Use Ajax - here I am on uncertain ground because, I do not know Ajax well and am not sure it is the right technology for the task at hand.

Could someone please tell me if I am on the right track, or if I should research elsewhere?