all servers are technically 'international' and the only 100% way to make sure you see only English is to find exclusively English Free Companies and Linkshells and turn off all other chats. which seems a little lame.

however, you will most likely find more English speaking folks on the Japanese legacy servers, or figure out where the Oceanic/Australian crowd is (I know there were two different servers in the talk but I didn't keep up with it)