grammatical number - Agreement of verb 'to be' and a singular noun after a plural noun

How does the subject-verb agreement work when a singular noun describes a plural one?
Of the following, which sentence is righter?

The computers is a good choice.

The computers are a good choice.

Is there a rule about these types of formations? Please explain.

Answer

A subject can be plural while a complement is singular.

We (Mom, Dad, my sister, and I) are a family.

is a good example.

The computers are a good choice.

is the only correct one. Not just "righter".

You cannot use a singular verb for a plural subject (noun). In colloquial English, sometimes the constructions "we was" + [plural nouns] / "there is" + [plural nouns] are used. But this is only colloquial.