But who is going to be Adora Belle Dearheart? Instantly I saw Lauren Bacall, for some reason.

Christopher Lee for Death, has to be.

Can't believe you're arguing about Vimes. He started out as Dirty Harry - it *has* to be Clint Eastwood (& yes, the man can act more than enough to encompass the way Sam has grown).

Can't argue with Geraldine James (Blott on the Landscape anyone?) for Lady Ramkin.

Katherine Hepburn would be a superb Granny W. (but Brian Blessed feels wrong as Ridcully - not big enough & too hammy).

I can go with Sid James for Nobby Nobbs, but Dibbler ought to be "Del Boy" David Jason. Nicholas Lindsay as Rincewind isn't perfect, but the best of the suggestions so far.

Alec Guinness beats Rickman for Vetinari in my book. Rickman isn't spare/spartan/economical enough, call it how you will (& I think Rickman is a genius!), in physique or manner.

Rickman, perhaps, for Greebo. Or Sean Bean. Or me!

Oliver Hardy for The Dean? Doesn't quite work, but no-one else has mentiond The Dean. There must be a part for Stan Laurel too, but he's halfway between The Bursar & Ponder Stibbons, for me. Lon Chaney for whatshisname, the old zombie git in the bath chair.

A young George Clooney for Victor Maraschino of Moving Pictures (presuming that Errol Flynn is not available).