The Star Wars Franchise. I love A New Hope, but it would be ridiculous to Eternal Sunshine just that movie.
Other standalone movies would be Oldboy, Martyrs and The Godfather.
I'd love to revisit Nirvana's Nevermind, Pearl Jam's Vitalogy and MF Doom's Mmmm Food with a new generation.
Imagine experiencing Joe Sacco's Palestine, Proust's Swann's Way, Harvey Pekar's American Splendor and Stephen King's Salem's Lot for the first time (again).
I genuinely love this thought experiment...