John Hughes (1950 - 2009) was one of the greatest director/writers, especially when it came to teenage problems and their angst. Now, I know Spider-Man has a lot of teenage angst, I think that the X-Men, in the original incarnation would have quite a bit of teenage problems and young person problems.
I don't really have a specific year for this movie, but it would definitely be around 1985 or 1986, somewhere at that time period.
Up first would be Professor Charles Xavier: Professor X.
Christopher Plummer has acted in many films, of which include "The Sound of Music" as Captain von Trapp, "The Man Who Would Be King" as Rupyard Kipling, and he appeared as Sherlock Holmes in the films "Silver Blaze" (1977) and "Murder By Decree" (1979). Plummer is a brilliant actor even a couple decades later.
Next we have Cyclops --
Rob Lowe appeared in the films, "The Outsiders", "Oxford Blues", and "St. Elmo's Fire". He's a terrific actor, especially as the older brother in "The Outsiders". I think Rob Lowe would be perfect as the leader of the X-Men.
And who would Cyclops be without Jean Grey:
Molly Ringwald might seem like an obvious choice, but she is a good actress who has been in a few John Hughes films, such as "Sixteen Candles", "Pretty In Pink", and "The Breakfast Club". She has a good range of acting going from "Pretty in Pink" to "The Breakfast Club".
And now we have that heavenly mutant Angel:
James Spader is another actor in a John Hughes film: "Pretty In Pink", where he plays one of the "rich kids". James Spader is a phenomenal actor, playing with a bit of arrogance and enough swagger to pull off Warren Worthington III.
Of course, one of the smartest mutants is Hank McCoy, aka Beast:
(This choice I'm really proud of!)
Robert Downey, Jr. appeared in the film "Weird Science", another John Hughes film, where he played Ian, a school bully. Robert Downey, Jr. is a talented actor who can bring a whole new layers to Dr. McCoy.
Now it's time for the ever-so-cool mutant Iceman:
Matthew Broderick was in the 1986 film "Ferris Bueller's Day Off" where he played the now-famous cool-teen who ditches school. He was cocky, witty, had that perfect charm about him.
Honestly though, in the 1980's, if I were to make a Marvel movie, I would pick him for either Iceman or Spider-Man, I think he would be perfect in both!
Now we come to the Brotherhood of Mutants:
First off we have the Master of Magnetism, Magneto:
Christopher Lloyd is famously remembered as Doc Brown in the "Back to the Future" franchise. While this might seem like an odd choice, Christopher Lloyd has played more serious roles, where he brought a shocking role, such as in the film "One Flew Over the Cuckoo's Nest" where he played Max Taber, and in the television shows "Law and Order" and "Fringe" (I know those didn't come out before 1986, but I thought it was good example of his acting).
Now we have his right-hand woman, Mystique:
This one I was a bit iffy about, but I think she has the acting chops to pull off Raven Darkholme. Other than appearing in "National Lampoon's Vacation", she was also in "The Sentinel" and "A Streetcar Named Desire". She would be pretty cool as Mystique.
Next we have Toad:
Jon Cryer, best known in the role of Ducky in "Pretty In Pink" would be great as the quirky, off-the-wall Toad. He can play sinister and creepy real well and would be a good slight comic relief.
Now we have the hot-headed Pyro:
Appearing in "The Breakfast Club" as the rebel Bender, Judd Nelson was reported to having a hot-temper, something he could channel into Pyro.
Now we have the speedster Quicksilver:
Andrew McCarthy starred in the John Hughes films "Pretty In Pink" as the rich kid/ nice guy and in "St. Elmo's Fire". Andrew McCarthy would absolutely be perfect for the role of Quicksilver.
And as for his sister, the Scarlet Witch:
Jennifer Grey is most memorable in the films "Dirty Dancing" as Baby and as Ferris Bueller's sister in "Ferris Bueller's Day Off". She's got that menace about her from Ferris Bueller and the intensity of Baby that would be perfect for the Scarlet Witch.
Next up is the biggest Brotherhood member -- Blob:
John Candy has been in the films "The Blues Brothers" and "Planes, Trains, and Automobiles". He is a funny guy -- extremely funny -- but I think he would be superb as the Blob.
Now we have the final member of the Brotherhood -- Mastermind:
Jonathan Schmock is known for playing the snooty maitre d'. I think he would be really great in the role of Jason Wyngarde, the master of illusions. I think he would become the main villain, starting out small under Magneto's rule, but soon branching out to something much worse.
I know this one isn't part of the Brotherhood, but I think it would be great to have Senator Kelly as an original antagonist of the X-Men, before Magneto's Brotherhood steps in. Senator Kelly:
Paul Gleason, better known as the Assistant Principal in the film "The Breakfast Club" and as the jerk cop in "Die Hard". He would be great as Senator Robert Kelly!
Well, that's my fan cast for if John Hughes directed X-Men. John Hughes was a great director and he is sorely missed.