There have a couple times that I have come across an answer in the low quality post queue where the real problem is the question. I have always opened and voted to close the question and mostly ignored the answer. Is this the best practice? What could I do better?
Thank you for helping to review.
What you're doing is good -- if the problem is the question then the community should address that. In addition to voting to close, consider whether it'd be helpful to do any of the following:
If you can fix the problem (often you can't, but if you can), consider an edit.
Leave a comment on the question explaining the problem, if nobody else has (or if someone has but you can explain in more detail).
Leave a comment on the answer alerting the author to problems in the question; maybe the answerer can help, and if nothing else you've given him a heads-up that things might be changing.
If the question isn't currently on the front page, meaning fewer people will come across it, bring it up in chat (or on meta) to get more eyes on it.
I always try to rescue the question if at all possible, either by suggesting edits, or, occasionally by doing a full rewrite myself in the case that I don't feel the OP will be able to do it (in that case I always leave a comment suggesting the OP revert if the edit is not satisfactory).
I do this even if there are no good answers on the question. In terms of the overall goals of SE, I think what serves it best is to have the questions framed in their best possible light whenever possible.