The thread is about film franchises, which strictly speaking is a film series. An adaptation of a book does not constitute a film franchise.
As to whether some films Maltin quotes are even remakes is questionable. Titanic is based on a historical event and not a remake of a previous film and not even a re-adaptation of a particular book. It's central plot is unique to its telling of the story. I might do another one for remakes when I have more time and feel anal again.
I will list sequels and I will note when films spawned a franchise or sequels. It's worth noting that even though films lead to sequels throughout film history, they were much less likely to end up on a top ten list in earlier decades.
There now are straight to video sequels to just about every Disney film, but I won't count them because they don't tell us much about franchises of the period, as they were only made over the sequel crazy last couple of decades.
http://www.filmsite.org/boxoffice2.html
since 2010:
8 sequels
The Hunger Games was announced as a franchise from the first film
A sequel to Alice in Wonderland is in the works
since 2000:
6 sequels/prequels
7 lead to further sequels/prequels, sequels are in the works for 2 more. Spiderman has already been rebooted.
since 1990
2 sequels/prequels
6 films spawned further sequels/prequels
since 1980
4 sequels
9 films in the charts would spawn further sequels/prequels
since 1970
no sequels
10 films would go on to spawn sequels
since 1960
1 sequel
4 would lead to further sequels.
since 1950
no sequels
no further sequels
since 1940
1 sequel
no further sequels
since 1930
no sequels
4 would lead to sequels
since 1920
no sequels
1 would lead to further sequels