ughhh...here are some FACTS...not my opinion...for the fanboys who still think Jug cant be stopped by Doom.
Uncanny X-Men #194
-Juggernaut was coming for Nimrod after Nimrod blasted him and destroyed his outfit.
-Nimrod used some kind of energy attack to pick Juggernaut off the ground he was walking on (yes stopped the Juggernaut) and blasted him through a building
-When Juggernaut got up he said:"Wow!, Aint never been hit so hard...I thought only the Hulk could pull a stunt like that"
-eventually, Jug. charged Nimrod, Nimrod sidestepped and knocked off Jug's helmet with one back hand...
-then Juggernaut said: "My helmet--but it's seal was s'posed to be unbreakable, Tom Promised!"
-Then without the his helmet, Juggernaut was blasted from Nimrod's eyes with "tight beam ultra high frequency sonics"
-once Jug was apparently ko'd...Nimrod used a neural dislocuter to keep his nerve impulses from reaching his body, leaving him limp and paralized
Jug. was clearly outmatched by Nimrod...Nimrod soundly beat him without argument, while fighting Rogue, Colossus, Wolverine, Nightcrawler, and Shadowcat...basically, Jug. got his ass kicked in a 6 on 1 fight against Nimrod.(My opinion)
In X-Men #56
-The Sentinel that was about to terminate Rogue and Joseph, was suddenly struck in the face with a blast and destroyed
-Then Doom is seen standing in front of it
-He says: "Still who but I could construct a gauntlet capable of destroying a sentinel with such precision? There is more genius in the palm of my glove than in the entire scheme of Onslaught..."
Thus Im pretty sure Doom's gauntlet/palm of his glove, was the source of the blast that destroyed the sentinel(my opinion)...I think he could easily take off Jug' helmet with a similar blast considering Nimrod easily swatted it off
In FF#320 Doom shot Hulk in the head with a neural scrambler that left the Hulk unable to walk, let alone fight Doom...the same tech that Nimrod used to take down Jug.
Conclusion: Doom has the same tech available as Nimrod to take him down, Jug can be hurt from the high frequency sonics and paralized by neural dislocation.