“1–2 minutes” or “1–2 minute(s)”

The plural is used to designate any non-singular quantity, including indefinite amounts.

E.g.

negative: I have negative two dollars.

zero: I have zero dollars

singular: I have one dollar

plural: I have four dollars. I have two and a half dollars.

indefinite: I have several dollars.

You may also express amounts in English using the partitive genitive (e.g. a quarter of a donut), in which case the whole and not the parts determine the number. So I may have a "quarter of a dollar" or "an eighth of two dollars."

Also, collectives often take a singular verb, especially in American English.

both "The Government is a governing body" and "The Government are a governing body" are correct, although the first is more common in America and the second in the UK.

All that to say that while you would always use the plural "dollars" when talking of 1-2 dollars, you may use either a singular or a plural verb according to whether the dollars are considered one thing or many.

1-2 dollars is enough for a candy-bar

1-2 dollars are enough for a candy-bar