There was a male-on-male kiss on the lips in the screen adaptation of Arthur Miller’s play *A View From the Bridge (1961), directed by Sidney Lumet.
Young Hedy Lamarr ran stark naked through the woods and into a lake in Ecstasy (1932). Antonioni’s Blowup (1966) had frontal female nudity during one of the photographic sessions.
Perhaps the first non-porn, non-ethnographic commercial feature with both frontal male and female nudity was I Am Curious (Yellow) (1967). The first U.S. non-porn commercial feature with male and female frontal nudity was Robert Forster and Verna Bloom in Medium Cool (1969).
Psycho (1960) may have been the first U.S. commercial feature in which we saw a toilet flush, but there were comic scenes in The Grapes of Wrath (1940) and Tarzan’s New York Adventure (1942) in which rubes are frightened by the flush of a toilet, just offscreen.
By the way, Richard Hooker’s novel and the 1970 movie are titled MASH. The film’s advertising and the TV series styled it MAS*H.
I really doubt that’s a French kiss between Rick and Ilsa in Casablanca (1942) (unless you mean they were in France at the time). The Production Code forbade it. Natalie Wood and Warren Beatty are generally credited with America’s cinema’s first open-mouthed kiss in Splendor in the Grass (1961).
First all-talking feature: Lights of New York (1928).
First feature entirely in widescreen: Fox Movietone Follies of 1929 (1929), now lost, unfortunately.
First 3-D feature in color: Robinson Crusoe (1946), from the U.S.S.R.
Twenty-six years before Anatomy of a Murder, Warner Bros.’ Footlight Parade used the word “panties” (and rhymed it with “scanties”) in the musical number “Shuffle Off to Buffalo”.