This site isn't important but the page is a curious example of how it can break a page to fix a bug.
In Opera the list can not be clicked. At all. The reason is that another part of the page covers it. You can not actually see this, because this part is invisible and has no content. It still prevents you from clicking…
For years, web designers have struggled with the problem that form elements did not disappear below other elements but always appeared on top. See this article for details:
So, when Opera finally fixes this problem you'd expect everyone to be happy. But oops.. that SELECT element on the above page won't work UNLESS you behave like IE and always put form elements on top of all other content.
Morale: there is always a page somewhere that DEPENDS ON even the most annoying bug in your rendering. Fixing bugs breaks pages. Period.