Marne-la-Vallée can be reached from Paris via car, train, or bus.
Communication shouldn't be an issue. Disneyland Paris is mainly French (social issue), but all menus and signs are also available in English (social issue) and some in other languages (social issues). All Cast Members speak English (social issue); and as they are recruited from all over Europe (social issues),several of them speak over 3 languages so you probably won't have a problem finding someone who speaks your language. If all else fails, the visitors are from all over Europe and the world (globalization), and a bystander might be able to translate. Many sights are also in English (social issue) and possibly German (social issue) as they are the 3 most common languages spoken in Disneyland. Maps are available in French (I'm not going to social issue all of them, I want to go to bed soon), English, Spanish, Italian, Dutch, and German while passing under the train tracks after you have purchased a ticket and entered the park.