toon is fine.
As long as it's not toon versions of the fantasy/medieval genre.
I'll try to simplifiy it for you:
Take a Lord of the Rings character and make them in a style other than the fantasy/medieval style portrayed in the books and movies.
The only other rule is to give the characters one of their character-defining items. Gimli with a beard and axe, for example. Now, there's no rule that it can't be a super-laser axe, but an axe all the same.
Hope that clears it up some.