Just an update on this - Our web teams are looking into some of the issues here.
We did do a migration of the Diablo 3 site to be more in-line with other Blizzard franchises. diablo3.blizzard.com is now the new URL for Diablo 3 and with this came a few hiccups that we are looking into.
RE: Regional selection for forums, we suggest using the footer at the bottom of the page to adjust language preferences which will redirect to said forums/pages.