First you will need to change your language.



Go to system settings:



Then console settings:



Then language:



Change it to what ever you want i used the last option:




Now load halo 3.

Matchmaking it will be the 3rd option down from the top.




If your going for achievements all you need is 4 people 5 for like 1 achievement. (lone wolves)


Now you will want to prefer language just hit "X" and its the last option as shown in the picture below:


Then have everyone your doing it with search at the same time and you should all get pared up.



Whats this? You want to go back to English??
well follow the pics below:




And pick English


That's how you do it.