I would have suggested EIEIO's idea too at first, so I didn't respond to this, but now I'd like to add that I use the latest version of Firefox as well to view these forums and have never had the problem you are describing. If it's a problem with Firefox, then it's because you most likely use an add-on I do not and that add-on may be messing with the forum code that runs in the background.
I'm guessing when you mention " I regularly get a "blank" screen with a message saying the connection was reset", that is a generic error screen.
So on a hunch, can you do me a favor and tell me what extensions are installed in Firefox? You can find them by clicking the Orange Firefox button in the top left and choosing 'Add-Ons'. That will open another tab. On that tab, select Extensions. Also can you jot down and let us know what User Scripts (if any) are installed? Lastly, while on that tab, I'd go through the plugins and look for anything 'out of the ordinary'.
Other than Firefox being the culprit, it wouldn't be the first time I saw a firewall/internet security program such as Norton, Mcafee, or AVG blocking certain websites.