The Large Display Paradox

Basic geometry question for anyone who might know, please.

I have used a 19" 4:3 LCD at the native 1280x1024 the past few years for my business apps. I’m not a programmer or designer, I’m just building a business but use a lot of apps from Office to video editing and web design. I’m considering going to a widescreen LCD (with WinSplit or GridMove and maybe a virtual desktop to manage the real estate). I use XP Pro and am not planning to customize its text sizing. I’ll always stay at native resolution with my LCD.

I’m trying to decide between going to a 19" at 1440 x 900, or a 24" at 1920 x 1200.

What I’m trying to find out is two things.

A. Which is going to give me the largest characters and how does that character size compare with what I have now?

B. If I go for the 24" will it end up giving me side-by-side Word docs that have text as big as what I get now?

Thanks.