First off, "To Catch a Thief", starring Grace Kelly and Cary Grant
Secondly, "Breakfast at Tiffany's", starring Audrey Hepburn and George Peppard
http://www.fanpop.com/spots/breakfast-at-tiffanys/images/9348327/title/promotional-photo
Next on the list is "Philadelphia Story", starring Katherine Hepburn, Cary Grant, and Jimmy Stewart
http://www.doctormacro.com/Movie%20Summaries/P/Philadelphia%20Story,%20The.htm
There are SO many more, like, "White Christmas", "Meet Me in St. Louis", "Calamity Jane", and so many others.
It mays me sad that no one today knows these movies. They are completely obsessed with "American Pie", "Scary Movie" or whatever other new movie that comes along. I miss movies that have real plots and good acting. Old movies are the best! We all need to watch more of them!