Best: "Home" and "Maison Des Lunes" from Beauty and the Beast, "She's in Love" from The Little Mermaid, "He Lives in You" from The Lion King
I can't really think of too many worst ones that have been ADDED, but there were certainly some egregious CUTS in the screen-to-stage transition...two that come to mind are "Sister Suffragette" in Mary Poppins and "The Morning Report" in earlier performances of Lion King.
"A Change in Me" (Beauty and the Beast), "I Want the Good Times Back" (The Little Mermaid), "He Lives in You" (The Lion King), "Anything Can Happen" (Mary Poppins), "For the First Time" (Tarzan), "These Palace Walls" (Aladdin)
"Oh look at the time, three more intelligent plays just closed and THE ADDAMS FAMILY made another million dollars" -Jackie Hoffman, Broadway.com Audience Awards
A lot of my favorites have been mentioned. I think "A Change in Me" is probably my favorite followed by "He Lives in You." There are definitely some underrated songs in Tarzan like "For the First Time" and "Everything That I Am." I also love "Made of Stone" from Hunchback and "A Million Miles Away" as well as "To Be Free" from the Aladdin show at California Adventure which I would have liked to hear in the Broadway production.
Someday from Hunchback (it played over the closing credits in the movie but was added to the show on stage and i like the music and lyrics better in the show compared to the pop version that played with the credits).
The description of the new songs in the Beauty and the Beast movie has me worried. I'll wait until I see it but those may end up being on my worst list. I don't even like the titles.
1. "If I Can't Love Her" from Beauty and the Beast
^^They better freaking put that one in the movie.
"
Alan Menken said they cut it from the movie and wrote a new song. He said it was a perfect song to end act 1, but wouldn't make sense in the middle of a movie.
"Someday" isn't really new, it was the song that was originally written to replace by "God Help the Outcasts" in the film but then the decision was reversed.
"Home" is one of my favorite Disney songs period. One of my least favorites is "The World Above" in Little Mermaid not because of the quality but because it robs "Part of Your World" of its impact imo.
"Contentment, it seems, simply happens. It appears accompanied by no bravos and no tears."
"He Lives in You" AND its reprise which I actually think is even better.
"Shadowland"
Pretty much all of the African music they added to Lion King
"These Palace Walls" - very underrated IMO. Easily my favorite song added to Aladdin, and one of the best melodies Menken has written in years.
"Practically Perfect"
I'm sad to say that, for the most part, I've found the rest of the added music to the Disney musicals to be pretty underwhelming. There are definitely exceptions - some good songs that I like but didn't mention above, but I think a large percentage of the additions over the years have been far outshone by the original songs.
"Home", "A Change In Me", and "If I Can't Love Her" definitely. Echoing others who said "He Lives In You" and the reprise. I'm actually quite partial to "Her Voice", if just as a lovely tenor song. "Made of Stone", certainly.
Does "Proud of Your Boy" count, since it was written for but cut from the movie? And "A Million Miles Away" is lovely as well.