I've been running the Secret of the Dragon Emperor-campaign and it's been going quite well. It's got a pulpy tone to the action; The shuffling of initiative each turn, random monster attacks, improvised weapons and high weapons damage keep things dynamic.
There's been a good few deaths so far...
I'd say it depends on the depiction of Donald, though usually he's the butt of any given joke. But Scrooge McDuck, particularly in his younger years, is both tough and very canny. So there are certainly competent adventurer ducks.