Could you use the Inspector feature to see what font Firefox is using? You can right-click an element and choose Inspect Element (Q). On the right side of the Inspector pane, click Font. (Screen shot attached.)

More generally, when you have a problem with one particular site, a good "first thing to try" is clearing your Firefox cache and deleting your saved cookies for the site.

(1) Bypass Firefox's Cache

Firefox menu > Preferences > Advanced

On the Network mini-tab > Cached Web Content : "Clear Now"

If you have a large hard drive, this might take a few minutes.

(2) Remove the site's cookies (save any pending work first). While viewing a page on the site, try either:

• right-click and choose View Page Info > Security > "View Cookies"
• Tools menu > Page Info > Security > "View Cookies"

In the dialog that opens, you can remove the site's cookies individually.

Then try reloading the page. Does that help?

Note that the Web Console (Firefox/Tools > Web Developer) shows a missing ';' in a style rule:

Expected end of value but found ':'.  Error in parsing value for 'font-family'.  Declaration dropped.

ul.MenuBarHorizontal li
{
	margin: 0;
	padding: 0;
	list-style-type: none;
	font-family: Urbana-Medium, Urbana-light, "Trebuchet MS", sans-serif /* missing semi colon */
	font-size: 100%;
	position: relative;
	text-align: center;
	cursor: pointer;
	width: 6em;
	float: right;
}