My list:
1. Sunset Boulevard
2. The Bridge on the River Kwai
3. Singin' in the Rain
4. On the Waterfront
5. All About Eve
Honorable mentions: Invasion of the Body Snatchers, North by Northwest
How about you?
In no particular order:
Giant
Sunset Boulevard
A Place in the Sun
White Christmas
Rear Window
My favourites:
the Green Man
To Catch a Thief
desk Set
Top Secret
the Happiest days of Your Life
My top 5
5. Sunset Boulevard
4. The Night Of The Hunter
3. The Searchers
2. Vertigo
1. Paths Of Glory
Honorable mentions: Singin In The Rain, Strangers On A Train, North By Northwest, Bridge On The River Kwai, The Seventh Seal, Rear Window, High Noon, Rio Bravo and On The Waterfront.