This is incredibly impressive. Theantilove from Deviantart has plotted out the locations of each location of every disney and pixar movie. Of course, the map is missing some movies that came out in the last few years, but it's amazing nonethenless.

NORTH AMERICA

Little Mermaid: Caribbean
Although the author and original story are Danish, the wildlife is clearly tropical. There is simply no way to have that type of flora and fauna anywhere near Denmark. It is very reasonable that The Little Mermaid movie could take place on the Danish colony, now known as the US Virgin Islands.(thanks so /u/theflyingbarney) Another big clue is the fact that in the beginning of the movie the storm is referred to as a "Hurricane." Something Europeans knew very little about. (thanks to /u/Cheesecakejedi)
Brother Bear: Northern Canada, Alaska.
The people in the movie are cast as Inuits, who inhabit both northern Canada and Alaska.
Meet the Robinsons: US/Canada.
Lewis mentions being from Canada but the tone of the family seems like they are American.
Bambi: Northern US/Canada.
Though originally a German story, the collection of animals clearly indicates North American wildlife. [from the bambi wiki] ""Disney took the liberty of changing Bambi's species into a white-tailed deer from his original species of roe deer, since roe deer do not inhabit the United States, and the white-tailed deer is more familiar to Americans.""
Fox and the Hound: Northern US/Canada
Although the feel of the movie definitely seems Appalachian, there are simply no Grizzly Bears in Appalachia, which would put the movie more north.
Chicken Little: US
Generally Midwestern American feel (corn fields are present) but no specifics given
Home on the Range: Western US
The movie takes place on a cattle ranch with several noticeable arch formations shown throughout.
Lady and the Tramp: North Eastern US
Small town America feel. Shown celebrating Fourth of July. A song sung in the beginning of the squeal puts the movie in New England.
A Bug's Life: Texas/Mexico Border
Due to the rainy season present in the movie and flight the grasshoppers take to summer in Mexico puts the movie close to the New Mexico/Texas southern border.
Icabod Crane: Sleepy Hollow
Explicitly stated
Oliver and Company: New York City, US
Explicitly stated
Pocahontas: Virginia, US
Explicitly stated
Incredibles: Midwest/Chicago, US
My logic for The Incredibles is based mainly on the design of the city. The city definitely does not have a West Coast or Midwestern feel, and my top two choices where either Chicago or NYC. I went with Chicago based on the following comparisons:
The elevated trains: The Incredibles vs Chicago Where it is true that NYC has elevated trains, Chicago is much more well known for them and the style of the ones in The Incredibles reflects the Chicago style.
The streets: The Incredibles vs Chicago Again, a definite Chicago feel, Chicago has a much more industrial feel to the city streets. City Profile/Water Front: The Incredibles vs Chicago I think this one speaks for itself. Parks/Foliage: The Incredibles vs Chicago
. In response to the Emeryville idea. The city is referenced twice: 1. The street names are real Emeryville street names 2. When Hellen activates the GPS in Bob's suit the GPS zooms in on the San Fran area. So it's impossible for it to be both his home town and where Syndrome's secret hideout it. Especially given the long plane ride they must take to get there.
Toy Story: Small Ohio town
The idea here was to place the Toy Story movies near Chagrin Fall, Ohio which is the popular theory for where they are located. It is based on the idea that it is the home town of Lee Unkrich(co-director of several Toy Story movies), and there is a Go Tigers sticker in Andy's room. (The mascot for Unkrich's high school.) The weather is also consistent with Ohio in that they get a heavy blanket of snow at/around Christmas.
Bolt: Hollywood
Explicitly stated
Cars: Arizona, US
Radiator Springs is found on Route 66, significantly East of Los Angeles, which would put it somewhere in Arizona.
Lilo and Stitch: Hawaii, US
Explicitly stated
Princess and the Frog: New Orleans, US
Explicitly stated
The Rescuers: New Orleans/ Bayou, US
Explicitly stated
Dumbo: Florida, US
Where he is "born" and a bulk of the movie takes place
SOUTH AMERICA
Emperor's New Groove: Peru
Explicitly stated
Up: Venezuela
Explicitly stated
Three Caballeros: Mexico, Brazil and Argentina
Explicitly stated

EUROPE
Robin Hood: England
Explicitly stated
The Great Mouse Detective: London, England
Explicitly stated
Sword and the Stone: England
Explicitly stated
Winnie the Pooh: England
Although the real life bear that Winnie the Pooh is based on is from Canada, the books are actually set in Ashdown Forest, Sussex, England.
Alice in Wonderland: England
Although never explicitly stated in the movie, the writer was Englishman Lewis Carroll.
The Adventures of Mr. Toad: England
Explicitly stated
Black Cauldron: Mythological Wales
The author, Lloyd Alexander, was inspired by Welsh mythology.
101 Dalmatians: London, England
Explicitly stated
Peter Pan: London, England
Explicitly stated
Cars 2: England
The last and big part of the movie is set in England.
Brave: Scotland
Explicitly stated
Snow White: Germany
The movie is not explicit enough to definitively decide its location, so the original work of the Brothers Grimm puts it in Germany.
Sleeping Beauty: France
This movie is based on the Charles Perrault version of this story, there is an abundance of fleur de lis, and the French national anthem is played to announce the arrival of Princess Aruroa. (thanks to /u/DrRegularAffection)
Pinocchio: Italy
An Italian story and they are near mountains by the sea.
Tangled: Germany
The movie is not explicit enough to definitively decide its location, so the original work of the Brothers Grimm puts it in Germany.
Cinderella: France
When they revamped It's A Small World, Cinderella was placed in France (next to the Cancan dancers and Eiffel Tower) with Jacques and Gus. Video Relevant @ 2:35. Also, one of the new Mickey shorts takes place in France and at one point we see Cinderella. (thanks to /u/rustylime)
Hunchback of Notre Dame: Paris
Explicitly stated
Beauty and the Beast: France
Explicitly stated
Aristocats: France
Explicitly stated
Ratatouille: Paris, France
Explicitly stated
Hercules: Greece
Explicitly stated
Atlantis: Mediterranean
The movie never explicitly states where the Atlantis they are heading for is. The best approximation would be the more historically proposed location which would be in the Mediterranean Sea. A common misconception with this location is that it should be Iceland; however Iceland is the location of the Shepard's Journal, not Atlantis itself.
Frozen: Norway
The presence of Norwegian architecture, art and landscapes (namely mountains and fjords) put in the movie in Norway.

AFRICA
Tarzan: Nigeria/Gabon
Although never explicitly stated, due to the wildlife and the proximity to the coast, the movie would have to take place in either Nigeria or Gabon.
Lion King: Kenya/Tanzania
The location of Mt Kilimanjaro and the Serengeti are located here.

ASIA
Jungle Book: India
Explicitly stated
Mulan: China
Explicitly stated
Aladdin: Saudi Arabia/Iran
Explicitly stated

AUSTRALIA
Rescuers Down Under: Australia
Explicitly stated
Finding Nemo: Great Barrier Reef
Explicitly stated

OTHER
Dinosaur: Pangea
Treasure Planet: Alternate Universe
Wreck-It Ralph: Cyberspace
Although the arcade has a location in the real world, the characters live in cyberspace, which is an alternate universe to ours.
Monsters Inc.: Alternate Universe
Wall-E: Future Earth/Space