No, the victim doesn't have to survive. And, we don't have to see the actual kidnapping.
Recap (I hope I got the numbers correct. )
K = Kidnapping
1. Ransom (Glen Ford)
2. The Night of the Following Day
3. Peggy Sue Got Married
4. Fatal Attraction
5. Seven Brides for Seven Brothers
6. The Godfather
7. Ransom (Mel Gibson)
8. Raising Arizona
9. Cats and Dogs
10. Manny and Lo
11. After Dark My Sweet
12. Fargo
13. Ace Ventura
14. The Black Marble
15. House Arrest
16. Ruthless People
17. The Happening
18. Nick of Time
19. King of Comedy
20. Man on Fire
21. Horse Feathers
22. The Man Who Knew Too Much
23. Ashanti (1979) kidnapped: Beverly Johnson
24. Spoorloos (The Vanishing, 1988) kidnapped: Johanna ter Steege
25. Io non ho paura (I'm not Scared, 2003) kidnapped: Mattia Di Pierro
26. The Cell (2000) kidnapped: Tara Subkoff
27. The Silence of the Lambs (1991) kidnapped: don't know the name of the actress
28. Shoot to Kill (1988) kidnapped: Kirsty Ally
29. Kidnapped (1960) kidnapped: James MacArthur (There are by the way many films based on the book by Stevenson)
30. The Golden Child
31. Sandokan, la tigre di Mompracem (1963) kidnapped: Geneviève Grad
32. Frantic