CALL ME MADAM - Great film and in many ways it improves upon the stage script. Also it's the only chance to see Merman in a musical comedy role the way she played it on Broadway
OKLAHOMA! - Fairly faithful and quite well sung
KING AND I - beautifully acted though not quite as faithful as OKLAHOMA!
LI'L ABNER - fairly faithful and fun film of the stage hit
WEST SIDE STORY - film is dated now but those techniques were cutting edge at the time.
SOUND OF MUSIC - better than the stage show, and the wonderful scenery counts for much. (though I miss "How Can Love Survive" and "No Way to Stop it.")
1776 - Excellent film adaptation, esp in the new restored version on DVD
GREASE - loses the small town atmosphere of the show (as well as what little authentic 1950s period sound there was) but gains in the performances and sheer fun
EVITA - about as good a film as could have been made of the show
CHICAGO - good film version (although nothing quite matches the stage original)
Cast albums are NOT "soundtracks."
Live theatre does not use a "soundtrack." If it did, it wouldn't be live theatre!
I host a weekly one-hour radio program featuring cast album selections as well as songs by cabaret, jazz and theatre artists. The program, FRONT ROW CENTRE is heard Sundays 9 to 10 am and also Saturdays from 8 to 9 am (eastern times) on www.proudfm.com