Some things about your CSS (but not a solution, oops)
1) Ian's right, you must use each ID only once.
2) Using the 'top' and 'left' properties without the 'position' property has no effect. May I ask what did you want to achive by assigning them a 0 value?
3) The 'vertical-align' property doesn't work here, because it aligns inline boxes inside an inline element, applying it to the container inline element. If you are not familiar with these terms, I can try to make it simpler through an example.
And the way to do it? If you know the size of the images, you can use absolute positioning. Or add them as backgrounds to the DIVs. And there are possibly other solutions.