The song is called L-O-V-E (go figure on that one...) and it's by Nat King Cole. It's not by Tony Bennot nor Frank Sanatra.

Nat King Cole recorded the song for his album of the same name, released in 1965. Cole himself did several versions, and in the following years, the song has been covered numerous times, including by artists , Cole's daughter Natalie Cole and Michael Bublé.

Just as much as the song was/is popular among musicians, the song is among advertisers. Thus, a number of commercials used the song. What specific one - still up to debate.