Resident Evil Zero
Albert Wesker and William Birkin spend most of the game here, watching Rebecca Chambers and Billy Coen as they make their way through the Umbrella Executive Training Center. Rebecca later visits the room briefly in order to retrieve the Up Key needed to activate the main turntable outside; however, upon taking the key two Hunters will attack her.
Resident Evil 2
Claire Redfield and Leon Kennedy visit the room several months later, again to retrieve the Up Key (initially referred to in-game as the Control Panel Key. After taking the key the T-00 will appear and smash the security camera before attacking the player.
Resident Evil: The Umbrella Chronicles
The Turntable Monitor Room only appears once, in the opening cutscene for Beginnings 1, where Birkin and Wesker discuss the current threat posed to Umbrella's existence while observing Billy Coen and Rebecca Chambers' traversing through the mansion, with the latter, deciding Umbrella was finished, deciding to walk away from Umbrella (while also informing Birkin about his mission to lure S.T.A.R.S. to the Spencer Mansion), to Birkin's chagrin before the latter decides to set the facility to self-destruct in order avoid more complications.