If you don't set a font at all, Times is the default web font.

It's not always about personal preference. You need to use a font thats going to work on all systems. Unfortunatly, there are only a handful.

The only one I see missing from this thread is Geneva.. I've never used it before though.

ariadnadionisos wrote:

http://psychology.wichita.edu/optimalweb/text.htm
From the page: "Significant differences in reading time were found  in that   Times New Roman and Arial were read faster than Courier New, Century Schoolbook, and Georgia. Fonts at the 10-point size were read more slowly than fonts at the 12-point"

its somewhat hard to believe a text thats supposedly about optimal web design when the text is reddish brown on a mustard yellow background - makes me want a hotdog!!