Should I still choose short stay even if I'm hoping to get 1-year visa?
Yes. A long-stay visa (also known as a "national visa" or a "type D" visa) is a visa that allows you to stay for longer than 90 days at once, which as you seem to be aware is not what a one-year multiple-entry visa allows. You're applying for a short-stay ("type C") visa, albeit one that is valid for multiple entries over a period of 1 year.
In other words, short-stay vs. long-stay refers to the conditions of your visits ("stays") rather than to the duration of the visa's validity.
You probably know this, but for the sake of completeness I will mention it nonetheless: with a one-year multiple-entry visa, your visits to the Schengen area will be governed by the so-called 90/180 rule, namely that for every 180-day period, you must have no more than 90 days of presence in the Schengen area.