If you got 0.3 req/s from wordpress, there was probably something wrong with your configuration or system. I run wordpress on absolutely ancient hardware via Apache SuPHP. It basically does a sudo + CGI-like exec per request. It still manages to squeeze out about 20 req/s.
Above setup was enough to withstand being at the frontpage of Hacker news. I'm guessing this website's problem is more related to Hostgator or whatever he's hosting it on. Perhaps a badly configured database backend.
