I'd say good ol' potato chips. You can get plain, BBQ, Sour Cream & Onion. A variety to satisfy most people. Another one I like is tortilla chips & have a jar of salsa opened up.
When I am with a group of friends or even just with family having a family evening the go to snacks are always potato chips, tortilla chips and dip and also popcorn. Loved by all and can't go wrong with those.