Much obliged for the help guys, thank you.
I've taken your advice and upgraded the firmware - I was fearing it would do something nasty but it went just fine.
Also loaded all the fonts mentioned and will try each in turn.
First impressions are I just love the Lucinda sans at 4th smallest, bold.
Not as much on a page as some, but the white space between the lines seems to make it more restful (don't know the psychology - or is it physiology of this - any opticians here?).
I'm assuming you just get used to turning the page more often. But I'll do a book in each and see how it goes.
ps while loading my ebooks, I noticed the eBooks file had two subfolders En and Fr.
Since I don't read French these days, if I knock those subfolders out and just put stuff under eBooks will that work the same?