Okay, let’s see…
First, the Fellowship:
Gandalf - French Stewart
Aragorn - Jason Alexander
Boromir - Randy “Macho Man” Savage
Legolas - Jeff Garlin
Gimli - Justin Timberlake
Frodo - Djimon Hounsou
Sam - Katt Williams
Merry - Vin Diesel
Pippin - Jason Statham
Elrond - Ray Romano
Galadriel - Melissa McCarthy
Arwen - Victoria Jackson
Theoden - Michael Cera
Denethor - Paul Reubens
And one that I think would be truly awesome:
Gollum - Al Pacino
Stars of Yesteryear, 1940s version…
Bilbo - Gregory Peck
Gandalf - Gary Cooper
Aragorn - John Wayne
Boromir - Cary Grant
Legolas - Errol Flynn
Gimli - Edward G. Robinson
Frodo - Jimmy Stewart (“Why, look-ee here Mr. Gandalf, now you know I don’t want to go off chasin’ after some confangled ring thingy! Why, M-Merry would throw a fit!”)
Elrond - Humphrey Bogart
Arwen - Ingrid Bergman*
Galadriel - Judy Holliday
Denethor - Lon Chaney Jr.
Theoden - Sir Lawrence Olivier
Sauromon - James Cagney**
Gollum - Peter Lorre
*… rowr…
** technically, Christopher Lee could have been cast in a late-1940’s version of LOTR, but he already had his chance.
Then again, Lorre would have been PERFECT for Grima Wormtongue. He practically built his entire career out of playing the part…
True. Perhaps Lon Chaney Jr. as Gollum and Orson Welles as Denethor, with Peter Lorre playing Grima Wormtongue.
The cast of M.A.S.H. (TV version, later years)
I will specify Alan Alda as Sauron. The rest, fit in as you will.
Harry Morgan would obviously have to be Gandalf
David Ogden Stiers as Gimli and William Christopher as Legolas
Gary Burghoff as Frodo
Jamie Farr as Sam
Mike Farrell as Aragorn
Loretta Swit as [del]all[/del] both of the female characters
Wayne Rogers as Boromir, McLean Stevenson as Theoden, and Larry Linville as Wormtongue - they all get killed off
Every character played by Eddie Murphy, Klumps-style.
I’d be curious why you’d think this. Based on other films I’ve seen those guys in Bean’s acting style is naturally bold, he’s a guy I could actually see slaughtering thousands of orcs in open battle and then stealth bragging: “I couldn’t have slaughtered those thousands of orcs had the rest of my men not kept the enemy’s 100 elite guard at bay.” Mortensen, on the other hand, has a more sneaky/stealthy demeanor. Not in a slimy way, but understated–like someone who has the personal charisma to bend the will of thousands of battle-hardend warriors but really prefers trusting his life only to his own abilities.
TLDR: Bean can yell clearly from his diaphragm like a combat leader (Osgiliath), Mortensen’s uvula gets in the way like someone who is less accustomed to wanting to be heard from quite a long way away.
Forgot one!
Samwise - Christopher Walken
Gandalf – Jeff Bridges (in his “Big Lebowski” persona)
Aragorn – Nick Nolte
Gollum – Sylvester Stallone
Frodo – Bryan Cranston
Sam – Leonardo di Caprio
Pippin – Kevin Costner
Merry – Aston Kutcher
Elrond – Brad Pitt
Galadriel – Taylor Schilling
Arwen – Kate Mulgrew
Gimli – Jason Biggs
Legolas – Bruce Campbell
Saruman – Bob Odenkirk
Boromir – Mickey O’Rourke
Theoden – John Goodman
Denethor – Stephen Colbert
Faramir – John Turturro
Nope. Both are perfect for the roles they did play.
Frodo: Kiefer Sutherland
Sam: Johnny Depp
Aragorn: John Goodman
Legolas: Danny DeVito
Gimli:Alexander Skarsgård
Gandalf: Steven Wright
Galadriel: Roseanne
Arwen: Nobody (she doesn’t appear in the book. 
)
Gollum: George Clooney
Steven Seagal as Bilbo
Chuck Norris as Frodo
Some additions to my original list;
Saruman - Robin Williams
Treebeard - Corey Feldman
Grima Wormtongue - Rick Moranis
Eowyn - Grace Park
Eomer - Dwayne Johnson
Faramir - Tom Felton
Samwise Gamgee - Jayden Smith
Frodo: Chevy Chase
Treebeard: Christopher Walken (“The…Ents ah…going…to woah.”)
Arwen: Sidibe Gabourney
Sauroman: Woody Allen
Gimli: Kareem Abdul Jabbar
Sam: Gilbert Gottfried
Strider: Rick Moranis
I think Ahhnold would make a great Stone Troll, and Rosie could be pretty good as Shelob (although Roseanne would be better).
Okay, now I’m imagining the argument scenes between these two characters.
I did Lord of the Rings Re-Imagined back in 2012 or so. Here is a link to my comic strip of the cast:
Gandalf - Bob Denver
Aragorn - Henry Winkler
Legolas - Jar Jar Binks (most of what Legolas does ic CGI, so go the whole way)
Frodo - Bob Hope
Sam - John Ratzenberger
Arwen - Roseanne Barr
Saruman - Rupert Grint
I can just see that scene: “Ahhhh… Mr. Frodo. Sir… I know a… Fine place that you…Can hide the ring! It’s the same place… Mr Bilbo… Kept his fathers watch… When he was captured by… The Orcs.”
Also:
Legolas: Yul Brynner
Feel free to adjust and advise–
Gandalf - Graham Chapman
Aragorn - John Cleese
Boromir - Terry Jones
Legolas - Eric Idle
Gimli - Michael Palin
Frodo - Simon Pegg
Sam - Nick Frost
Merry - Rowan Atkinson
Pippin - Tony (Baldrick) Robinson
Elrond - Hugh Laurie
Galadriel - Prunella Scales
Arwen - Carol (Zoot) Cleveland
Theoden - Brian Blessed
Eowyn - Connie Booth
Saruman - Terry Gilliam
Gollum - Andrew (Manuel) Sachs