she is one protective momma!
thats good though, nothing dare cross her babies, or feel the wrathe of MONSTER KILLER MOMMA DUCK!
I'd go ahead, and atleast try to take the baby chicks away, before her eggs hatch, chances are hers will hatch at night, and by morning they'll be out and about. or she'll get bored, thinking no more eggs will hatch, and leave the nest.
one of my mallard hens is sitting right now, and she gets down right nasty if I bug her, she becomes a puffy hissing MOMMA FROM HECK!