TOD: For home viewings, the most movies I've watched in one day were those of Fred Astaire and Ginger Rogers. I used to treat myself to a Fred and Ginger day on the occasional weekend when I was living in Naples, Italy.
I'd watch:
The Gay Divorcee
Follow the Fleet
Top Hat
Swing Time
Carefree
Shall We Dance
The Barkleys of Broadway
Other weekends, I might do a "Die Hard" festival followed by a "Lethal Weapon" festival. During those years, there were only three movies in each series on home video. I'd also do the occasional "Rocky" festival and watch the first four movies.