1. The Roaring Twenties
2. Angels with Dirty Faces
3. The 39 Steps
4. King Kong
5. Bride of Frankenstein
6. The Public Enemy
7. Scarface
8. Wuthering Heights
9. Each Dawn I Die
10. 'G' Men

Preference order would depend on mood and day, so I'm presenting my list alphabetically:

• All Quiet on the Western Front (1930)
• Gold Diggers of 1933 (1933)
• The Old Dark House (1932)
• Penthouse (1933)
• The Petrified Forest (1936)
• Private Lives (1931)
• Red Dust (1932)
• Top Hat (1935)
• Waterloo Bridge (1931)
• The Wizard of Oz (1939)

Here are my favourites, not in any order though:

1. The Thin Man 1934
2. Imitation of Life 1934
3. Love Affair 1939
4. It Happened One Night 1934
5. Ninotchka 1939
6. You Can't Take it With You 1939
7. The Adventures of Robin Hood 1938
8. Dark Victory 1939
9. Top Hat 1935
10. Shall We Dance 1937

These are not necessarily my Top 10, but most are not listed above:

1. King Kong (1933)
2. The Wizard of Oz (1939)
3. Gone With the Wind (1939)
4. Frankenstein (1931)
5. Modern Times (1936)
6. Mutiny on the Bounty (1935)
7. Snow White and the Seven Dwarfs (1937)
8. City Lights (1931)
9. Dracula (1931)
10. Mr. Smith Goes to Washington (1939)

Good answers, all.

Guess I'll go with ten very rewatchables and then go from there....

1. Libeled Lady (1936)
2. Theodora Goes Wild (1936)
3. Mad Miss Manton (1938)
4. Walking on Air (1936)
5. Wise Girl (1937)
6. Thanks a Million (1935)
7. Stage Door (1937)
8. Alexander's Ragtime Band (1938)
9. Follow the Fleet (1936)
10. Imitation of Life (1934)

Whatttt? Somehow that list came out inverted, but the point is that it wouldn't be the 1930's without Irene, Claudette, Miriam, Myrna, Ann, Ginger, Lucy, Alice and Stanwyck.

So, through in some Fonda, William, Milland, Ameche, Haley, Raymond, Powell, Powell, Power, and there you have a great start.

• Imitation of Life (1934)
• Follow the Fleet (1936)
• Alexander's Ragtime Band (1938)
• Stage Door (1937)
• Thanks a Million (1935)
• Wise Girl (1937)
• Walking on Air (1936)
• Mad Miss Manton (1938)
• Theodora Goes Wild (1936)
• Libeled Lady (1936)

After newly thinking about it, I wish to revise my list (further above) a bit. Following (listed chronologically by years) are probably the top favourites in my 1930s films DVDs collection:

• All Quiet on the Western Front (1930)
• Private Lives (1931)
• Smart Woman (1931)
• Waterloo Bridge (1931)
• The Old Dark House (1932)
• Red Dust (1932)
• Gold Diggers of 1933 (1933)
• Top Hat (1935)
• Dodsworth (1936)
• The Wizard of Oz (1939)

It could easily wind up, in a different week or month, certain ones of those titles feeling like they should be switched out with certain other ones. Several fave collected alternates, that on any given day could either equally or even better "hit the spot," include:

• Blonde Crazy (1931)
• The Miracle Woman (1931)
• King Kong (1933)
• Penthouse (1933)
• Anne of Green Gables (1934)
• The Black Cat (1934)
• The Goose and the Gander (1935)
• The 39 Steps (1935)
• The Petrified Forest (1936)
• These Three (1936)
• The Prisoner of Zenda (1937)
• The Lady Vanishes (1938)
• Love Affair (1939)

Really, everything listed is more or less interchangeably my favourites - just all depends on the day, the mood, and the energy level.

TMDbers' Fave Silent films lists: https://www.themoviedb.org/movie/643/discuss/5a32308ec3a36814ae011f9b

TMDbers' Fave 1940s films lists: https://www.themoviedb.org/movie/1585-it-s-a-wonderful-life/discuss/5a321d3cc3a36814b9010202

In no particular order:

1930:

The Divorcee

Anna Christie

The Bat Whispers

The Devil to Pay!

Holiday

Morocco

Raffles

1931:

Arrowsmith

Dracula

Frankenstein

The Front Page

The Sin of Madelon Claudet

1932:

One Way Passage

A Bill of Divorcement

Grand Hotel

The Mummy

Murders in the Rue Morgue

Tarzan the Ape Man

Vampyr

1933:

Cavalcade

Dinner at Eight

The Bitter Tea of General Yen

Gold Diggers of 1933

Little Women

1934:

The Thin Man

Evelyn Prentice

Manhattan Melodrama

Fashions of 1934

Of Human Bondage

Anne of Green Gables

Baby Take a Bow

Little Miss Marker

Bright Eyes

Imitation of Life

Tarzan and His Mate

1935:

Escapade

Star of Midnight

Captain Blood

Bride of Frankenstein

Curly Top

The Little Colonel

Our Little Girl

The Littlest Rebel

Magnificent Obsession

Dangerous

The rest of the 30's

1936:

After the Thin Man

My Man Godfrey

The Great Ziegfeld

Libeled Lady

Dodsworth

Craig's Wife

These Three

Stowaway

Dimples

Poor Little Rich Girl

Captain January

Reefer Madness

1937:

The Awful Truth -- https://www.youtube.com/watch?v=NbJVYtFwcHA (best part starts at 1:55)

Double Wedding

The Last of Mrs. Cheyney

Grand Illusion

Lost Horizon

Snow White and the Seven Dwarfs

Topper

Wee Willie Winkie

Heidi

1938:

A Christmas Carol

The Adventures of Robin Hood

Bringing up Baby

Jezebel

You Can't Take It with You

The Lady Vanishes

Little Miss Broadway

Rebecca of Sunnybrook Farm

Just Around the Corner

Blondie

Holiday

1939:

Another Thin Man

The Women

Dark Victory

The Wizard of Oz

The Old Maid

The Private Lives of Elizabeth and Essex

Goodbye, Mr. Chips

Made For Each Other

Wuthering Heights

Ninotchka

The Little Princess