as a small series of compilations for the playstation that lasted for five discs, namco museum offered several games on each disc, and for each one you could walk in a virtual museum and look at an interactive history of the games, such as promotional artwork, merchandise, and game tips taken from the arcade cabinets.
the museums also had their own wings for the games which you could go in as they have their own layout and you could walk into what looks like the original cabinets and play the games from there.

unfortunately though, volume 4 and 5 seem pretty rare, as they cost more these days than the first three