Thanks for your reply! Oops, I forgot I removed the Doctype, I was trying something out, and now when I try and add it back in, it makes it display even more wrong! Aaargh!
Anyway, it turns out the guy has an 800x600 screen resolution ... bugger! I'm looking for a quick fix, since he's probably way, way in the minority and I don't want to have to re-build the whole site. Does anyone know of a quick, easy way, possibly using php to say that if screen resolution is 800x600, then all elements on page should be, say, 70%???