Little Inferno is fun, short and literally impossible to lose.

Stick it to the Man has a fun, whacky story and central cocnept, and is also super-easy.

I don't know, there are VN's out there that take a lot of time to read through, 30h+. The hard part is because of all the bugs. :P

.. and you might not be able to see all the different branches & endings in one readthrough.

Yeah, I hate it. :P
One decision may be the difference between the bad, gloomy ending and the perfect ending.
An example:
In front of you, a lone, shiny flower...do you want to pluck it?
> Yes
> No
> Scream at it!

I suggest Limbo, even though it's not that easy I'm afraid...

You forgot otions no. 4 and 5:
> Take a picture of it
> Make a selfie

True, but it's designed so that trying something over is relatively simple. It has checkpoints but they aren't spaced out at impossible intervals.

Crap, I did, but option 4 results in a bad end, as the flower is camera-shy.

Is there a kind of game you would like?

Braveland is a pretty simple tactical RPG, it will take you less than 7 hours to complete.

Brothers: A Tale of Two Sons is brilliant and short.

A Bird Story is a prequel-ish to To The Moon and is very short, but is not as good as TTM. Still worth a play though.

The Shivah is a pretty short point & click. The Last Door Season 1&2 are as well.

Human Resource Machine is a programming puzzle game and is around 8 hours of game.

Her Story should take you 2-3 hours. Dear Esther and Gone Home are both under 4 hours for a walking sim.

Neverending Nightmares a single play will only take you a couple of hours, but there are multiple endings to play for if you like it.

Virginia is weird and short.

DEFCON - each match is short. Playing against the computer is pretty easy.

Bastion is short, and not too hard, and I hear other people like it.

Enigmatis and Nightmares from the Deep are two hidden object game series and worth a look.

[Guilty disclaimer] Actually I haven't played it, so I don't know if it fulfills the criteria the OP established. But it is definitely short!

Mainly games I can play with a controller right now.

Thanks everyone!