The One Where No One Proposes - S9-E1
Visible crew/equipment: When Mr. Geller, Ross, and the others are looking at Emma lying in the bassinet in the nursery, in the shot facing the adults as the camera zooms in we can see the edge of the set wall (with clouds and stork) behind them, and the set lighting is visible at the top right corner of the screen.
The One Where No One Proposes - S9-E1
Visible crew/equipment: At the beginning when they're looking at Emma between shots you can see a Cameraman or Camera in the Window.
The One With the Pediatrician - S9-E3
Visible crew/equipment: When we first see Joey and Mike at the restaurant we can briefly see a boom mic above them. (00:08:25)
The One With the Male Nanny - S9-E6
Visible crew/equipment: When Chandler says "pity laughs," all the stage lights are reflected in the pots behind him. (00:20:50)
The One With the Male Nanny - S9-E6
Visible crew/equipment: After Rachel and Ross hire the new nanny, when it cuts to Chandler walking into Joey's apartment, we can see the opening in the wall beside the door.
The One With Ross's Inappropriate Song - S9-E7
Visible crew/equipment: When Monica comes home at the end, as Joey pulls her down on top of Chandler as to protect her eyes from seeing the tape, you can see a knee pad on Courteney Cox's knee, under her skirt. (00:14:20)
The One With Ross's Inappropriate Song - S9-E7
Visible crew/equipment: While Chandler and Joey are watching Richard's videotape, when Chandler's relieved it's just football he heads off to get beer, and in the next shot as he hears the sound of moaning we can see the opening in the wall behind the TV.
The One With Ross's Inappropriate Song - S9-E7
Visible crew/equipment: When Joey jumps on Chandler to shield him from seeing Monica's sex tape, the mat they land on is visible prior to the scene.
The One With Rachel's Other Sister - S9-E8
Visible crew/equipment: When Monica heads to Joey's apartment to get the pies Joey tells her it's just one pie now, and after Monica's comment about losing the will to scold we can see the hole in the wall beside the front door.
The One With Rachel's Other Sister - S9-E8
Visible crew/equipment: When Monica tells Joey that he has a red plate instead of a fancy plate because it's a game, just as Joey says that he can't believe he won, we can see the camera at the right side of the screen.
The One With Rachel's Other Sister - S9-E8
Visible crew/equipment: When Amy says, "Stupid Thanksgiving," a boom mic can be seen above Rachel's head.
The One With Rachel's Phone Number - S9-E9
Visible crew/equipment: In the scene where Chandler pretends that he just got home from Tulsa and meets Joey who is waiting in the hallway outside the apartment, the camera cuts between Chandler and Joey. Every time the camera shows Chandler, there is a wooden wall at the left edge of the screen with an orange tape. This is evidently part of the set, because when the camera cuts to Joey, the wooden wall with the orange tape is nowhere to be seen. (00:16:45)
The One With Rachel's Phone Number - S9-E9
Visible crew/equipment: After Chandler has climbed down the fire escape and shows up in the hallway where Joey's been waiting with a baseball bat, when they both walk into the apartment the opening in the wall can be seen beside the door. We can see the opening again after Joey finds Chandler's suitcase.
The One Where Monica Sings - S9-E13
Visible crew/equipment: When Gavin goes to the door to bring Rachel soup you can see a camera man's microphone in the top of the screen. (00:10:50)
The One Where Monica Sings - S9-E13
Visible crew/equipment: After Joey dips his finger into the hot wax and smears it all over his hands, when Sonya walks out of the back room we can see her tape mark on the floor, which she promptly steps on.
The One With The Blind Dates - S9-E14
Visible crew/equipment: At the start in the coffee shop there are some stage lights visible in the coffee pot behind Joey. (00:00:05)
The One With The Blind Dates - S9-E14
Visible crew/equipment: When Phoebe meets Joey to tell him about the date for Rach, the stage lights are seen outside the coffee-shop. (00:05:35)
The One With The Mugging - S9-E15
Visible crew/equipment: Just before Ross and Phoebe walk into Central Perk after being mugged, as it shows the window from the outside you can see a stage light between the blinds. (00:10:35)
The One With The Mugging - S9-E15
Visible crew/equipment: When Chandler first walks into the conference room at work, and also later when he walks out of the conference room while using a cane, the end of the set wall can be seen at the left side of the screen.
The One With The Mugging - S9-E15
Visible crew/equipment: When Ross walks into Central Perk and Phoebe asks him about his class before she tells him the truth, in the closeup of Ross the camera can be seen at the right side of the screen.
Answer: The painting doesn't have a name, and if it does it is never mentioned in this episode.