This first is one of the more charming love songs, from the 1951 musical A Tree Grows in Brooklyn. It's performed by Shirley Booth, who won an Oscar for the powerful drama, Come Back, Little Sheba (for which she'd also won a Tony Award), but is probably best-known for the 1960s sitcom Hazel, which ran for five seasons. Oddly, her performance in A Tree Grows in Brooklyn is considered one of the reasons for the who's only mediocre, disappointing run of 267 performances. Not because she was no good, but because it was only a supporting role, Aunt Sissy, and she was so wonderful they refocused the show more around her character which imbalanced the story. Here's one of her numbers, "Love is the Reason," written by Dorothy Fields and Arthur Schwartz.
This is one of the funnier love songs. It comes from the 1961 musical Little Me that starred Sid Caesar in a tour-de-force performance, playing around half a dozen roles. For this character, he plays the incredibly wealthy Noble Eggleston telling his love Belle (played by the show's heroine, Virginia Martin) how much "I Love You,", despite their one huge difference, which he explains. The show has a score by Carolyn Leigh and Cy Coleman.