Superman has never beaten Dr. Manhattan. Honestly, it wouldn't have made sense considering how easily Manhattan dismissed DC's superheroes sans the Trinity. Manhattan is on a different level; yes, even from Superman.
Gladiator can't one shot Juggernaut.
No, Hyperion is Marvel's take on Superman (exact same powers, very similar origin, etc). Sentry only resembles Superman in really superficial ways (fast, strong, durable, can fly), but their characters and abilities are pretty different beyond that.
Honestly, that shyt is goofy. Not because Juggernaut beat Hulk, but how he did it. You mean to tell me that Professor Hulk was fooled by Juggernaut in street clothes? Dumb shyt.