The One With Ross's Sandwich - S5-E9
Revealing mistake: Joey's bucket of chicken is, rather obviously, a KFC bucket with "Finger Lickin' Chicken" stuck over the original KFC lettering - you can even see the picture of Col. Sanders. (00:17:10)
The One With Ross's Sandwich - S5-E9
Continuity mistake: After Joey makes up the story about how he slept with Monica once in London, in the shots facing Phoebe, Rachel, and Ross the door to Monica's apartment goes back and forth being either wide open or closed, depending on the angle of the shot.
The One With Ross's Sandwich - S5-E9
Continuity mistake: During the literature class, when they're discussing Wuthering Heights all the writing on the blackboard changes, and the word "conflict" is first spelled correctly, but then it's spelled without the letter L.
The One With Ross's Sandwich - S5-E9
Character mistake: Joey tells Chandler and Monica that Rachel found the underwear in Monica's sofa. It was actually Phoebe who pulled them from the sofa and held them up.
The One With The Inappropriate Sister - S5-E10
Visible crew/equipment: At the start as Joey comes out, watch the tv and you will see a line of stage lights. (00:00:05)
The One With The Inappropriate Sister - S5-E10
Continuity mistake: Ross and Joey are discussing Joey writing his own moviel; Ross sits down to begin writing, and Joey places a beer on the table next to him. The large part of the label is facing to the side, but it then switches to facing the front without being touched. (00:06:20)
The One With The Inappropriate Sister - S5-E10
Continuity mistake: When Rachel and Monica are arguing about her meddling, Monica raises her hand to her face and you see a sparkly engagement ring on her finger. Her character wasn't engaged but Courteney Cox was at the time. (00:07:05)
The One With The Inappropriate Sister - S5-E10
Continuity mistake: Joey and Chandler are playing 'Fireball'; Joey puts his hand through the wall next to the fridge, then in the next scene the hole is gone with no trace. (00:08:50)
The One With The Inappropriate Sister - S5-E10
Continuity mistake: Rachel goes into Danny's apartment and we see that his door opens up right into his living room. However, in "The One With The Yeti", we see Danny's apartment from outside the door and there is a wall directly behind him. (00:11:00)
The One With The Inappropriate Sister - S5-E10
Continuity mistake: Phoebe is complaining about people disrespecting her charity bucket, and hands the bucket to Monica as she does so. In the first two shots Monica holds the bucket by its edge, but when the camera goes back to her for a third time, she is holding the bucket by its handle. (00:11:35)
The One With The Inappropriate Sister - S5-E10
Visible crew/equipment: When Ross and Monica are wrestling, the stagelights can be seen in the tv. (00:12:45)
The One With The Inappropriate Sister - S5-E10
Continuity mistake: When Phoebe is being removed from her "bucket spot" she starts to take off the signs she has put up. With the camera close up to her, she rips one off, then the camera changes to a wide view, and she is suddenly holding two signs. (00:16:40)
The One With The Inappropriate Sister - S5-E10
Visible crew/equipment: When the passerby drops his lit cigarette in Phoebe's charity bucket, the end of the department store facade can be seen at the left side of the screen, and later when Phoebe hands off the bell to her replacement the end of the right side facade can be seen as well.
The One With The Inappropriate Sister - S5-E10
Continuity mistake: When Joey and Phoebe are talking to each other on the couch, Rachel tucks her hair behind her ears, but in the next shot it's moved.
The One With The Inappropriate Sister - S5-E10
Continuity mistake: When Joey is talking to Ross about him being an actor, the shot changes and Ross is holding his beer in a different position.
The One With The Inappropriate Sister - S5-E10
Continuity mistake: When Rachel and Monica are talking about Danny and the girl on the subway, Rachel has tiny bits of her fringe hanging out and it moves between shots without any movement.
The One With All The Resolutions - S5-E11
Continuity mistake: During the countdown to midnight, just as everyone says, "Happy New Year!", the camera cuts to Phoebe and Ross. In the background Joey and Rachel open their arms to hug each other; the camera cuts to just Joey and Rachel and they open their arms again. (00:01:00)
The One With All The Resolutions - S5-E11
Continuity mistake: When Ross first enters Elizabeth's bathroom, the lotion is first in line on the shelf; next to it is something else and then the powder. Later, the powder is first in line on the shelf and the lotion has moved. (00:09:30 - 00:12:45)
The One With All The Resolutions - S5-E11
Continuity mistake: When Joey and Rachel are trying to work out if the other knows about Monica and Chandler, they sit at the table in silence. In a side shot of Joey they look at each other sneakily, and Joey has his arms by his sides. It then cuts to a head-on shot of Joey, and he's got his right arm over the back of the chair. (00:19:00)
The One With All The Resolutions - S5-E11
Visible crew/equipment: Monica and Chandler leave the apartment to go "do laundry," then Phoebe heads out to the airport. When Joey takes a seat, the reflection of camera movement is visible on the window, above the sink. Then Rachel and Joey tell each other they can't share what they each know, and just as Rachel sits down beside Joey, once again we can see the reflection of camera movement above the sink. (00:19:30 - 00:20:20)
Answer: The painting doesn't have a name, and if it does it is never mentioned in this episode.