With Peking duck, you just eat the skin, maybe with a sliver of meat. You'd place that on a thin pancake, with shreds of spring onion and cucumber, and some of the sauce and wrap it up like a cigar to eat.
Hong Kong style roast duck will be chopped up in small pieces before served. You might even see some places chopping them up in front of the window or by the counter.Sometimes they may debone it if westerners don't fancy nibbling at the bone, but we prefer to have it served in the bone.
Hope you get to try it some time