On my web pages, I tend to match the "normal" font size to that of the windows font. So I guess it doesn't matter what screen resolution other people are running because it would appear to be "normal" to them anyway. There will always be people that changed the fonts to the windows menus etc to what they want and as good a mind reader that I am, I just don't know what the user does with the fonts on their system. And I think at least if I set the fonts of the website similar to the standard system fonts then it would suit the majority of users.