Ooh, love your idea of telling which of the novels you've read. I hadn't thought about it but I really have read a lot of these books as well. I'll put some of my recommendations/comments under a spoiler so as not to run the thread too far off track.
Spoiler
I love 101 Dalmatians by Dodie Smith. I haven't read the sequel yet. I think it's called Twilight Bark.
Fox and the Hound book has a fox and a hound and there the similarities end.
The Rescuers is a cute book. I think the reason Disney made Rescuers Down Under is because the books have a series so they were toying with the idea of making the movies a series as well (even though the original Rescuers movie doesn't follow the first Rescuers book).
The Sword in the Stone novel can be found as part of The Once and Future King, which was originally 4 separate books (the first being The Sword in the Stone) but they put it together in one volume (if it's the one I'm thinking of).
Bedknobs and Broomsticks is also different from its movie but fun.
I recommend James and the Giant Peach because it's Roald Dahl and I find him amusing.
Spoiler
The only novel I've read that is a source of a Disney film is Bambi. I didn't like the book at all Without giving too much away there are parts that are more graphic than the Disney film and the deer that Bambi fights over Faline with has a bigger role.
I've also heard that Disney was considering making more Rescuers movies since there were several books in the series but eventually decided to make Chip n Dale Rescue Rangers instead.
Ponyfan
I completely forgot about the Pete's Dragon remake, argh! Sorry about that X_X I think cause it was more realistic-looking than the original, I just mentally file it in with the live-action remakes.
Re: novels
Spoiler
101 Dalmatians is a great book, I love the sequel Starlight Barking too - it's bonkers and I definitely see why Disney decided to go in a different direction for their sequels, but I like it anyway :p Sadly I think it's hard to find now (not sure if it's still in print or not), I remember having difficulty tracking it down when I bought my copy.
I've read Peter Pan and Jungle Book, but only once each, and it was so long ago I can't really remember much about them.. I've read at least some of the original Alice books but not sure if I've read all of either one.
for Rescuers, I have the first three books in one of those "3 books in 1" deals.. don't usually like those, but I found it in a charity shop and figured, why not. They misprinted it and put the stories in the wrong order >_> I remember liking them okay (it's been a while and I only read through it once ^^;) but I preferred the films... wasn't a fan of how the books handled the romance between Miss Bianca and Bernard. Definitely wouldn't pass up the other books in the series if I found them in a charity shop too, but I don't think I'd go out of my way to get them.
I have also read most of the books that the Classics were based on.
Spoiler
Snow White and the Seven Dwarfs (1937) - yes
Pinocchio (1940) - yes
Fantasia (1940)
Dumbo (1941) - yes
Bambi (1942) - yes
PACKAGE FILM/WARTIME ERA
Saludos Amigos (1942/1943)
The Three Caballeros (1944/1945)
Make Mine Music! (1946)
Fun and Fancy Free (1947)
Melody Time (1948)
The Adventures of Ichabod and Mr. Toad (1949) - yes
SILVER AGE
Cinderella (1950) - yes
Alice in Wonderland (1951)- yes
Peter Pan (1953)- yes
Lady and the Tramp (1955)- yes
Sleeping Beauty (1959)- yes
101 Dalmatians (1961)- yes
The Sword in the Stone (1963)- yes
The Jungle Book (1967)- yes
BRONZE/DARK AGE/EARLY RENAISSANCE
The Aristocats (1970)
Robin Hood (1973)- yes
The Many Adventures of Winnie the Pooh (1977)- yes
The Rescuers (1977)- yes
The Fox and the Hound (1981)- yes
The Black Cauldron (1985)- yes
The Great Mouse Detective (1986)- yes
Oliver & Company (1988)- yes
THE DISNEY RENAISSANCE
The Little Mermaid (1989)- yes
The Rescuers Down Under (1990)
Beauty and the Beast (1991)- yes
Aladdin (1992)- yes
The Lion King (1994)
Pocahontas (1995)
The Hunchback of Notre Dame (1996)- yes
Hercules (1997)- yes
Mulan (1998)- yes
Tarzan (1999)- yes
EXPERIMENTAL ERA/POST-RENAISSANCE
Fantasia 2000 (1999/2000)
Dinosaur (2000)
The Emperor's New Groove (2000)
Atlantis: The Lost Empire (2001)
Lilo & Stitch (2002)
Treasure Planet (2002)- yes
Brother Bear (2003)
Home on the Range (2004)
Chicken Little (2005)
Meet the Robinsons (2007)
MODERN DISNEY
Bolt (2008)
The Princess and the Frog (2009)- yes
Tangled (2010)- yes
Winnie the Pooh (2011)- yes
Wreck-It Ralph (2012)
Frozen (2013)
Big Hero 6 (2014)
Zootopia (2016)
Moana (2016)
Ralph Breaks the Internet (2018)
Frozen II (2019)
Raya and the Last Dragon (2021)
Encanto (2021)