However, I like the idea of discussing the pros and cons of various actors for various parts, in that it gives people an idea of how other people visualize the characters. In this spirit, I have a few pointless suggestions of my own:

Peter Cushing = Denethor

Patrick Stewart would be good at anything, but I like Elrond best.

I've heard people suggest Alec Guiness for Gandalf before, but I disagree. However, I think he would be perfect as Theoden.

Aragorn, Faramir, Boromir, Eomer, Imrahil, Glorfindel = who cares? There will be plenty of hunky leading men to choose from. Just reserve the prettiest actors for elves and the more rugged ones for humans.

Galadriel, Arwen, Eowyn, Goldberry = same idea. Find a great looking babe who can actually act. Catherine Deneuve (sp?) is too old now for Galadriel... How about Bjork for Goldberry?

Robin Williams = Tom Bombadil (end of discussion)

Saruman = how about Vincent Price?

Gandalf.....John Gielgud (sp?) except he's too old and frail (he made a dynamite Prospero, though); Sean Connery could be appropriately blustery, but I think his face is wrong.

What do you think of the idea of an Asian actor playing Legolas? Wood elves are supposed to be more exotic and elfin looking than high elves.

One of the toughest parts will be finding enough dwarfs to play the hobbits who both can actually act and look right. Unless the perfect Frodo is found, the result will be disaster.

Also, I think Gollum will be far harder to pull off than an ent. The costume will have to withstand very close scrutiny, and it will need to convincingly express human emotions in a way that an ent need not.

Well I think I'm out of ideas. Ciao!