My favorite Superman collected editon of all has to be Tales of the Bizarro World
This unique series ran in Adventure comics in the early 1960's and to say it was interesting and funny doesn't do it justice. Everything was game when it came to being Bizarroed - television, movies, baseball, morals/virtue and the traditional family life (via late 1950's/1960's Father Knows best family life) and that's just the tip of the iceberg. The creative team included Jerry Siegel, Wayne Boring, and Curt Swan a Superman All Star creative team to be sure. This was truly auilty pleasure.
Tales of Bizarro world was replaced in issue 300 by another Superman related feature - Legion of Super-Heroes and Bizzaro just wasn't quite the same in the years to follow (except the classic Yellow Lantern/Bizarro JLA).