DVD Express is often wrong on dual-layered/dual-sided discs. A Bug's Life is indeed single sided - however that gold sheen you're seeing is a dual-layered disc. This means there are two data layers on the one side of the disc which can hold up to 9gb, as opposed to a single layer which holds 5gb. Dual-layered discs are very common right now. Eventually there will be dual-layered, dual-sided - holding 18gb!