You have two options: DHTML, which allows you to specify the pixel position of an element on the page, or a table. The latter would be my preference. You need to create a table with a width of 100% and a height of 100%. Then you need three rows and three columns, the top left, top right, bottom left and bottom right cells containing your images. The remaining cells also need a width and height of 100% to make sure they become as large as they can to fill the window and push the cells containing the images to the edges of the window.
If you need the precise table code let me know.
--
moto