I don't think Donkey Kong would be a bad idea. The character is iconic and most people know Donkey Kong even older adults.

And his personality is not so set in stone so they may have a little more leeway, plus characters like Diddy, Dixie, and Cranky would probably work well in an animated kids feature.

Get the Kung Fu Panda or LEGO Movie writing team to write it. Get a real team of Hollywood writers to do it, keep it far away from a niche US studio or a Japanese one. 

They could introduce Mario at the end if the goal is to make a Nintendo 'universe', lol.

Then once Nintendo has their feet wet with that they could move on to Mario and Zelda, so DK would be a pretty good test run.

That said I'm pretty sure Nintendo has a deal with Sony for a Mario CG movie, there were pictures of Miyamoto and Iwata (before his passing) with Avi Arad, the producer who was making the film for Sony, so I dunno, I think that deal is already done.

Sony was trying to get the rights for Pokemon and Smash Brothers movies also, but it looks like Warner Bros. may have outbid them on Pokemon. 

Nintendo has already made a movie and that was Super Mario Brothers. Most of there IPs have already made the step in the movie industies like Pokemon, Pikmen, Zelda, Star Fox etc. (Referring to Cartoon series and Mini Series aswell) Your title is misleading since it wont be Nintendos first movie.

If Nintendo was going to make a movie i would love to see a Metroid Movie.

Xenoblade should be their first movie.

Kimishima basically said they will not make live action movies, but instead animated movies.

Metroid, Zelda, Lugi Mansion, Pikmin, StarFox, Mario, Donkey Kong...they are relly all good choices for animated movies.

Maybe just make a CGI movie based on a brand new premise. They have the money and the ability. They would just need a western writer and director

Fire Emblem, Metroid, Zelda and potentially starfox could be done well.

I really don't see how a Mario movie could possibly work.

A live real Zelda - after games of Thrones.... everything is possible!

Live action Zelda.

Since it'll be Nintendo's first, best to go big or go home.

I don't think the source material doesn't give way to a Game of Thrones-style story, maybe something similar to Lord of the Rings, which isn't bad at all.

I'm actually more curious to see if this means their games will include more voice acting as in real languages and actual words n conversations, even if it's just Kirby RBA style (everyone talks but the main character). Man I really hope so, I feel games like Pikmin and Animal Crossing would really benefit.