Purgatory
(1999)

Turns out the town of "Refuge" is based on the biblical Purgatory.

All the main characters in the town are actually people stuck in Purgatory.

The gang of criminals that show up (accompanied by Sonny, a young, green kid) are all confronted by Wild Bill Hickcock, Billy the Kid, Jessie James, Doc Holiday, and Sonny. The gang is killed off and sent to Hell. The heroes, which all assumed they would be sent to hell due to killing the gang are sent to heaven. Sonny is killed in the last battle, and is offered a ride to heaven, but he opts to stay and wait on his love interest, Rose, to get into heaven with him.

Thanks Sam (The Light)!