In regards to points verses pixels, my suggestion is to always use points. This accomplishes a few things, including putting Netscape users in a very close appearance to the IE users since Netscape has chosen another display method. Furthermore, the point sizes are a closer relative to the print versions and tend to present a better-printed version.
Oh, and many times, the CSS validators out there go too far back in their versioning schema, thus producing errors that are probably not valid with the current browsers. Just a suggestion, but you might want to take a good look at TopStyle Pro for your CSS management and cleanup.