From the Super Mario Wiki
The Dining Room (Japanese: 食堂 Dining Room) is one of the rooms encountered in Area Two of Luigi's Mansion.
To gain entry to the Dining Room, Luigi uses the Key from the Conservatory. After entering, Luigi vacuums up several banana peels with his Poltergust 3000. He then finds Mr. Luggs, who is eating at the table. After Luigi captures Mr. Luggs, the lights come on and a treasure chest with money and a Silver Diamond inside appears.
The Dining Room is a largely symmetrical room, with the long table in the centre flanked by two china cabinets and two torches.
Ghosts in The Dining Room
Ghosts in The Dining Room during the blackout