Regarding your second question on screen size/resolution, I still believe that 800x600 is the de facto standard. That means almost anyone can use it -- and if your tables dynamically reallocate, it'll fill any sized screen.
I am forced to use 800x600 on my computer that powers the video projector -- and, yes ... I do look at web pages on the big screen for a variety of reasons.
I have two new laptops that will not go higher than 1024x768, so that's my "rock-bottom outside limit" for designing bigger sizes.
And I work with a designer who insists that sites should be designed at 464x280 !!! Why? Do the initials PSP mean anything? Nintendo DS? Blackberry? Yup, people want their browsers wherever they are, and the more portable and multi-functional, the better.
Really, it's a "do your own thing" world -- your design always comes back to your demigraphics. Where are all of your potential customers? What screens and devices are they likely to aggregate toward? How many can you risk alienating by picking a screen size that forces them to scroll horizontally?
Michael -
heavener@heavenr.com