The movie watched by Fontaine Khaled (Dame Joan Collins) and Nico Cantafora (Antonio Cantafora) on the flight to London is The Stud (1978).
Dame Joan Collins (Fontaine Khaled) is the elder sister of Jackie Collins, who wrote the 1979 novel of the same name on which this movie was based.
This is the movie that inspired Aaron Spelling to cast Dame Joan Collins as Alexis Carrington in Dynasty (1981).