i loved Nanny McPhee... Imelda was also in national lampoons blackball which was funny as all heck. Also from Nanny McPhee is Emma Thompson (who played the title role) as Professor Sybil Trelawney.
As far as how Umbridge will look in the new HP movie will debend on what special effects will have done before it's release. but here is one offical still showing her.. at least she is in pink - but where is her bow????