This site is highly inacessible, and no effort has been made to cater for non-standard users. this is probably a violation of your US section 508 as well as the uk disability discrimination act...
{jesus - you dont even have RELATIVE font sizes}
I recommend you get an accessibility audit quickly !
http://www.erigena.co.uk are highly recommended.
It is quite true: there are a lot of accessibility issues on site. The type-size issue you refer to is due to your browser setup by the way (see http://www.chessatwork.com/board/showthread.php?threadid=15824). If you have limited vision, you should definitely override site-specific font sizes wherever you can,
Other issues (such as Alt tags on images and so on) are still a problem from blind users for example.