Used to

[pne]

What spelling do you use in the following sentences?

NB For the purposes of grammar, please answer with what you would say (i.e. I'm looking for best written approximation of spoken English, not "standard written English" answers).

Also, I see that the "When it started out" sentence is not a good example; please disregard the exact wording and choose what you would use for the negative of "used to". (Can anyone suggest a good example? "When we were kids, we didn't used to have this sort of thing", perhaps? I can't think of a good example off the top of my head.)

And in general, I'm not asking whether you'd use the exact wording in a given sentence, but trying to elicit which form of "used to" you'd use in a given situation.

[Poll #430362]