The Rembrandt House Museum is definitely more 'house' in the traditional sense, than 'museum' in the traditional sense. I'd say it's about 80% period rooms, and 20% gallery space.
This building was Rembrandt's actual home and has been decorated to 'recreate the atmosphere' and interior as it would have been in his day. Using written records they were able to equip the home with accurate period furnishings... and they know exactly what each room was used for and were able to faithfully recreate them all.
There's a printmaking studio with a working press where they still print some of his actual plates. They give mini-lessons to the public showing how he made his etchings and drypoints, as well as examples of how he would have ground up his pigments and created various paints. There's a painting studio upstairs with large north-facing widows (yielding perfect northern exposure, which is the ideal lighting source when painting indoors from nature) where he would have taught his students and painted his sitters.
There are rooms filled with junk and ephemera... shelves of busts and swords and seashells and stones... the sort of compulsive collection of 'things' that we associate with either ADHD or light-hoarding. But understandable for an artist (I can sympathize) whose repetoire of models and knicknacks represents a bevy of things to draw.
There's a bedroom with his bed still intact (built into the wall). All in all, you get a very cozy feel for the life he led. For a while, anyway... he didn't ultimately keep his home, and he died penniless having outlived all 3 of his children and both of the great loves his life; his wives.
The downfall of Rembrandt is a mighty and storied thing... one of those tales that seems more parable than fact. But whatever the truth, for 20 years he lived here... the happiest and most productive years of his life were spent here... and it's a treat to visit.