I’ve always preferred serif fonts -- things like Times New Roman and Courier -- and I try to encourage my clients to use them. These days, I’d say more of my clients use sans serif fonts (like Arial), so pushing serif fonts is an uphill battle. (I recently had one client demand use of Verdana, a font that I wasn’t familiar with. When I asked why they wanted Verdana I was told it is the font the company adopted for its web site, but my client didn’t know why. Interestingly, since then I read somewhere else that Verdana was specifically created for web text, so I guess greater minds than mine have decided that.)
Anyway, having given up the battle for serif fonts, lately I’ve taken up a new cause: fighting against using black backgrounds and white (or, worse yet, yellow!) text on web sites. I’ve come across a number of sites with black backgrounds lately and they drive me crazy because they are very hard to read. I don’t want to name any sites here (but if you drop me an e-mail, I’ll give you an example), but I’m sure you’ve seen some yourself.
Please -- however boring it may seem -- stick to white, or light coloured, backgrounds with dark coloured text. Your readers will thank you. (Actually, that’s a lie. Your readers will not thank you if you use a white background because they won’t notice it. But believe me, they will notice -- and be very frustrated -- if you use a hard-to-read dark background with white text.)