@smeehee said:
Alternate title countries and language
With foreign language movies many of the have an English alternative title that is classed as World Wide title
but this option isn't available when entering it instead you have to just pick an English speaking country.

Translated by Google.
Films that have a "worldwide" title, usually this title is added in Alternative Titles, specifying the country of origin and which is a "worlwide" type title.
So, if a search is made for that Alternative worlwide title, the movie will be found.
I will try to find an example and post here if and when I find it.

Is it possible to add World Wide to the option of countries you can choose from?

I don't think so, but I don't decide that. It's Travis Bell, the creator of TMDb.

Also on the home page you have to select a language that the original film was released in

Not necessarily.
You will normally see the movie page in the language you specified as your language on your Profile.
If there is no translation for your language then you will probably see the data in the original language
and if it does not exist in the original language, you will see it in English.
You only change the language if and when you want to see the data in any other language.

but there are movies with no dialogue so again you have to choose something that isn't correct.

The Original Language refers not only to the dialogues but also to the initial and/or final credits
and in some silent films, the subtitles or frames with the text of the characters' "lines".
In addition, Orginal Language is historically used by the system to inform/define the origin of the Movie.

Is it possible to add no dialogue to the list of languages available?

What has already been discussed is to use the term "no dialogue" in the spoken languages field, at the bottom of the film data page.
But I confess that I do not remember the arguments or what was decided.

EDIT
It seems to me that the option "no language" in "Spoken Languages" was accepted
A good example is the film The Artist (2011)
https://www.themoviedb.org/movie/74643-the-artist

EDIT 2
World-wide
https://www.themoviedb.org/movie/354556/edit?active_nav_item=alternative_titles&language=en-US
https://www.themoviedb.org/movie/208763-viy/edit?active_nav_item=alternative_titles&language=en-US