I have Vista too, and I have the same specs as you said above. I really thought it was something wrong with my PC, so I used System Restore to manufactured settings. Now I have the same problem, so it must be something wrong with this site.
I can post, but at the bottom of the page it says how long does it take to generate a page and it went from 0.98 secs to 5.98 secs. That is horrible considering there is hardly no one on the site right now.