Everything is now all lined up and even - but I have to scroll back and forth to see it all. My monitor is 17 inch and my display properties are set at 800x600. I viewed the code source and see that the table is indeed set at 800 pixels width.
Here is what I think is going on: the jpgs in the center are 457 pixels wide (slightly more than the allotted 50% ratio) - thus pushing the limits of the center table.