What is the name of the movie that opens with a corpse and a funeral and what is the name of the actor that played the corpse and what is the song that is playing during the opening?

The Big Chill, Kevin Costner and ........I Heard it Through the Grapevine (I Think)?

The Big Chill. Kevin Cosner and The Rolling Stones...You can't Always Get What You want.

"You Can't Always Get What You Want" is a song by the Rolling Stones, written by Mick Jagger and Keith Richards. Rolling Stone named it the 100th greatest song of all time in 2004 in its "500 Greatest Songs of All Time."

This song was first recorded in 1969 and appears on the Let It Bleed album featuring the London Bach Choir, a boy's choir. An instrumental version of this song is used at Alex's funeral in the movie The Big Chill.

https://en.wikipedia.org/wiki/You_Can%27t_Always_Get_What_You_Want

The corpse whose arm is shown in the movie's opening scene was "played" by Kevin Costner. He was cast in the role of Alex, the character whose suicide drew the friends together for the reunion. When the part was cut from the film, Costner was promised a role in Kasdan's next film.

https://en.wikipedia.org/wiki/The_Big_Chill_%28film%29

Beer1121 is right about "I Heard it Through the Grapevine" playing in the opening. The Stones song is played at and after the funeral, but the opening credits are "grapevine"

Sorry, I wasn't clear. An instrumental version of "You Can't Always Get What You Want" was played at Alex's funeral. "I Heard it Through the Grapevine" is, indeed, played during opening credits.