zipzap McDonald's lemonade is Sprite Zero:
Carbonated Water, Citric Acid, Flavourings, Sweeteners (Aspartame*, Acesulfame K), Preservative (Sodium Benzoate), Acidity Regulator (Sodium Citrate).
Fruit Shoot:
Water, Fruit Juices from Concentrate (Apple 6%, Blackcurrant 2%, Plum), Citric Acid, Acidity Regulator (Sodium Citrate), Natural Colour (Anthocyanins), Natural Flavouring, Preservatives (Potassium Sorbate, Dimethyl Dicarbonate), Sweeteners (Acesulfame K, Sucralose), Antioxidant (Ascorbic Acid).
Neither is exactly perfect nutritionally but I fail to see how one is full of crap and the other isn't!
OP I'd go for burger, fries and Fruit Shoot all round. The ones who don't like the burger will eat the fries.