Haha. It's even hard for me to get my question formulated. I mean as characters. I guess it's hard to distinguish because in the movies/show the characters themselves are actors and performers.
The Muppet Movie is the origin story so I assume that comes first, and then perhaps the Muppet Show run, then after that they go to college, then Take Manhattan, etc.
Well it would sort of look like this....
The actual Muppet Movie was the story on how they got together then they went to work on The Muppet Show.
Now the other movies are complicated, some people say that The Great Muppet Caper and The Muppets Take Manhatten are ones that they're acting in those but using their actual name. For example in TMTM Kermit and Piggy get married but there's no reference to that anywhere else. Also in an interview once with Kermit, when someone asked if they're actually married he said "Well that was just a movie". So it's very complicated.
So if you wanted a timeline it'll basically look like this.
The Muppet Movie (actual story)
The Muppet Show 1-3
The Muppet Movie (the one they sit down to watch)
The Muppet Show 4-5
The Muppets (2011)
Those are basically the movies that they're not acting in, becuase The Muppet Show exists in The Muppets and it doesn't exist anywhere else not even in The Muppet movie becuase it wasn't started yet.