Use http://validator.w3.org/ to check your errors and sort them out before doing anything else.
In some cases you have position: absolute divs inside other position: absolute divs and I don't think this helps. Try closing off each div before you start the next if they are all position: absolute.
The object with the calendar is 168* 193px but is inside a div 100*199px.
If you reduce the window size, a lot of divs disappear off the left side of the screen. The div holding the text has left: -193px which is causing the text to move out to the left in a smaller window in IE7.
Remember that in your page all position: absolute divs take a position from the window (viewport) edges and because you have many with a right position they take a position from the right edge so that if the window size is reduced, they all move to the left, sometimes off-screen.
Your main div has align="middle" so that will move as the screen size varies but the position: absolute divs move separately unless the main containing div has position: relative. This causes the position: absolute divs inside it to take positions from the containing div edges instead of the window edges which may help you.
Code downloaded to my PC will be deleted in due course.
WIN7; IE9, Firefox, Opera, Chrome and Safari for Windows; screen resolution usually 1366*768.
Also IE6 on W98 with 800*600 and IE8 on Vista 1440*900.