"She's a Lady" by Tom Jones.
Here's why:
* Nice 'n Easy ads: Often feature upbeat, classic songs.
* "She's a Lady": This song is iconic, upbeat, and speaks to a woman's confidence and style. It was used in a very memorable Nice 'n Easy commercial in the early 1990s.
* Woman with red shoes: This is the detail that helps it stand out and helps to recall the commercial.
While other songs might fit some parts of the description, "She's a Lady" is the most probable answer given the context of a Nice 'n Easy ad.