in disneyland resort paris you can find everything in french and english. park maps with informations even in some more languages. sometimes you don't need to speak at all. you can choose what you want to eat by pictures. i don't speak french and i never had problems. you will be okay with english. the most shows are a mixture of english and french. hope you will have a great time in disneyland!
Don't worry you will be fine. Park maps are available in all the main European languages. Restaurant menus are in both French and English and many CM's also have very good English. The occassional Merci, Bonjour will hold you in good stead.