Don't feel like arguing so maybe this:

1. Jennifer Jones - The Song Of Bernadette
2. Paul Lukas - Watch on the Rhine
3. Joseph Cotten - Shadow of a Doubt
4. Ingrid Bergman - For Whom the Bell Tolls
5. Jean Arthur - The More the Merrier
6. Greer Garson - Madame Curie
7. Joan Fontaine - The Constant Nymph
8. Roger Livesey - The Life & Death of Colonel Blimp
9. Katina Paxinou - For Whom the Bell Tolls
10. Mickey Rooney - The Human Comedy

11. Joel McCrea - The More the Merrier
12. Gary Cooper - For Whom the Bell Tolls
13. Charles Coburn - The More the Merrier
14. Joan Fontaine - Jane Eyre
15. Henry Fonda - The Ox-Bow Incident
16. Humphrey Bogart - Sahara
17. Walter Pidgeon - Madame Curie
18. Deborah Kerr - The Life & Death of Colonel Blimp
19. Akim Tamiroff - For Whom the Bell Tolls
20. Ida Lupino - The Hard Way

1942
1. Humphrey Bogart - Casablanca
2. Ingrid Bergman - Casablanca
3. James Cagney - Yankee Doodle Dandy
4. Greer Garson - Mrs. Miniver
5. Carole Lombard - To Be or Not To Be
6. Agnes Moorehead - The Magnificent Ambersons
7. Katharine Hepburn - Woman of the Year
8. Bette Davis - Now, Voyager
9. Gary Cooper - The Pride of the Yankees
10. Claude Rains - Casablanca

11. Monty Woolley - The Pied Piper
12. Ronald Colman - Random Harvest
13. Walter Pidgeon - Mrs. Miniver
14. Joseph Cotten - The Magnificent Ambersons
15. Spencer Tracy - Woman of the Year
16. Rosalind Russell - My Sister Eileen
17. Teresa Wright - The Pride of the Yankees
18. Greer Garson - Random Harvest
19. Gene Kelly - For Me and My Gal
20. Van Heflin - Johnny Eager

1942
1. Humphrey Bogart - Casablanca
2. Ingrid Bergman - Casablanca
3. James Cagney - Yankee Doodle Dandy
4. Greer Garson - Mrs. Miniver
5. Katharine Hepburn - Woman of the Year
6. Agnes Moorehead - The Magnificent Ambersons
7. Carole Lombard - To Be or Not To Be
8. Bette Davis - Now, Voyager
9. Gary Cooper - The Pride of the Yankees
10. Claude Rains - Casablanca

11. Monty Woolley - The Pied Piper
12. Ronald Colman - Random Harvest
13. Teresa Wright - Mrs. Miniver
14. Joseph Cotten - The Magnificent Ambersons
15. Walter Pidgeon - Mrs. Miniver
16. Teresa Wright - The Pride of the Yankees
17. Susan Peters - Random Harvest
18. Gene Kelly - For Me and My Gal
19. Tim Holt - The Magnificent Ambersons
20. John Mills - In Which We Serve

Van Heflin - Johnny Eager is from 1941.

So:

1. Humphrey Bogart - Casablanca
2. Ingrid Bergman - Casablanca
3. James Cagney - Yankee Doodle Dandy
4. Greer Garson - Mrs. Miniver
5. Carole Lombard - To Be or Not To Be
6. Katharine Hepburn - Woman of the Year
7. Agnes Moorehead - The Magnificent Ambersons
8. Bette Davis - Now, Voyager
9. Gary Cooper - The Pride of the Yankees
10. Claude Rains - Casablanca

11. Monty Woolley - The Pied Piper
12. Ronald Colman - Random Harvest
13. Teresa Wright - Mrs. Miniver
14. Joseph Cotten - The Magnificent Ambersons
15. Walter Pidgeon - Mrs. Miniver
16. Teresa Wright - The Pride of the Yankees
17. Susan Peters - Random Harvest
18. Gene Kelly - For Me and My Gal
19. Tim Holt - The Magnificent Ambersons
20. John Mills - In Which We Serven

1941
1. Orson Welles - Citizen Kane
2. Humphrey Bogart - The Maltese Falcon
3. Joan Fontaine - Suspicion
4. Peter Lorre - The Maltese Falcon
5. Gary Cooper - Sergeant Yorke
6. Barbara Stanwyck - The Lady Eve
7. Humphrey Bogart - High Sierra
8. Greer Garson - Blossoms in the Dust
9. Bette Davis - The Little Foxes
10. Walter Huston - All That Money Can Buy

11. Robert Montgomery - Here Comes Mr. Jordan
12. Barbara Stanwyck - Ball of Fire
13. Olivia de Havilland - Hold Back the Dawn
14. Cary Grant - Penny Serenade
15. Gary Cooper - Ball of Fire
16. Sydney Greenstreet - The Maltese Falcon
17. Donald Crisp - How Green Was My Valley
18. Joseph Cotten - Citizen Kane
19. Walter Brennan - Sergeant Yorke
20. Van Heflin - Johnny Eager

1941
1. Orson Welles - Citizen Kane
2. Humphrey Bogart - The Maltese Falcon
3. Joan Fontaine - Suspicion
4. Barbara Stanwyck - The Lady Eve
5. Gary Cooper - Sergeant Yorke
6. Peter Lorre - The Maltese Falcon
7. Bette Davis - The Little Foxes
8. Humphrey Bogart - High Sierra
9. Robert Montgomery - Here Comes Mr. Jordan
10. Greer Garson - Blossoms in the Dust

11. Walter Huston - All That Money Can Buy
12. Barbara Stanwyck - Ball of Fire
13. Olivia de Havilland - Hold Back the Dawn
14. Cary Grant - Penny Serenade
15. Gary Cooper - Ball of Fire
16. Joel McCrea - Sullivan's Travels
17. Donald Crisp - How Green Was My Valley
18. Joseph Cotten - Citizen Kane
19. Lon Chaney Jr. - The Wolf Man
20. Veronica Lake - Sullivan's Travels

Good list, Bruno. Maybe this:

1. Orson Welles - Citizen Kane
2. Humphrey Bogart - The Maltese Falcon
3. Joan Fontaine - Suspicion
4. Barbara Stanwyck - The Lady Eve
5. Gary Cooper - Sergeant Yorke
6. Peter Lorre - The Maltese Falcon
7. Humphrey Bogart - High Sierra
8. Bette Davis - The Little Foxes
9. Greer Garson - Blossoms in the Dust
10. Walter Huston - All That Money Can Buy

11. Robert Montgomery - Here Comes Mr. Jordan
12. Barbara Stanwyck - Ball of Fire
13. Olivia de Havilland - Hold Back the Dawn
14. Cary Grant - Penny Serenade
15. Gary Cooper - Ball of Fire
16. Joel McCrea - Sullivan's Travels
17. Donald Crisp - How Green Was My Valley
18. Joseph Cotten - Citizen Kane
19. Lon Chaney Jr. - The Wolf Man
20. Sydney Greenstreet - The Maltese Falcon

Fine by me.

1940
1. Katharine Hepburn - The Philadelphia Story
2. Charlie Chaplin - The Great Dictator
3. Henry Fonda - The Grapes of Wrath
4. James Stewart - The Philadelphia Story
5. Laurence Olivier - Rebecca
6. Joan Fontaine - Rebecca
7. Bette Davis - The Letter
8. Cary Grant - His Girl Friday
9. Rosalind Russell - His Girl Friday
10. Ginger Rogers - Kitty Foyle

11. Cary Grant - The Philadelphia Story
12. James Stewart - The Shop Around the Corner
13. Raymond Massey - Abe Lincoln in Illinois
14. Margaret Sullavan - The Shop Around the Corner
15. Martha Scott - Our Town
16. John Carradine - The Grapes of Wrath
17. Walter Brennan - The Westerner
18. Judith Anderson - Rebecca
19. Jane Darwell - The Grapes of Wrath
20. George Sanders - Rebecca

Honestly I think Cagney could be #1. There's no question that Casablanca is the best film of the year, and the performances are a huge part of what makes it great, but Cagney's performance was a tour-de-force that supported the entire movie, and is considered his career-best.

Good job.

1. Katharine Hepburn - The Philadelphia Story
2. Charlie Chaplin - The Great Dictator
3. Henry Fonda - The Grapes of Wrath
4. James Stewart - The Philadelphia Story
5. Laurence Olivier - Rebecca
6. Joan Fontaine - Rebecca
7. Bette Davis - The Letter
8. Cary Grant - His Girl Friday
9. Rosalind Russell - His Girl Friday
10. Ginger Rogers - Kitty Foyle

11. Cary Grant - The Philadelphia Story
12. Martha Scott - Our Town
13. James Stewart - The Shop Around the Corner
14. Raymond Massey - Abe Lincoln in Illinois
15. Margaret Sullavan - The Shop Around the Corner
16. John Carradine - The Grapes of Wrath
17. Walter Brennan - The Westerner
18. W.C. Fields - The Bank Dick
19. Jane Darwell - The Grapes of Wrath
20. James Stephenson - The Letter

William Holden in “The Bridge on the River Kwai”?

I think Cagney can be promoted to #2 but I'd prefer to keep Bogie at #1. That role is just legendary.

How high do you see him, Bruno?

Maybe #17 or #18.