- You can center text vertically in a container, but NOT on the browser window. The web is not designed for centering objects on the screen vertically. Web pages start at the top, and grow down enough to display the content. Different browsers, screen resolutions, and window sizes make it impossible to center objects on the screen in a way that works on all computers.
- Don't use pixel counts to define sizes. Use points or percentages.
- Divs are box objects, not text containers. Use p tags for text.
That doesn't work on all browsers, because different browsers interpret the height of the body as a container differently. Some use the height of the content, others use the height of the window, and still others ignore a height attribute entirely when the container is the body.
The btable style won't even be the same in IE and FF. FF will render it 2 pixels larger in all directions than IE will.