Actually, after reflecting a bit more, I realize that my original posting was incomplete. At the time I experienced the lights I was actually experimenting with a variant of the Mahasi method suggested by Patrick Kearney. The main distraction for me, as for him, consists of thinking. He recommends an exercise of following the thoughts as the object of meditation, attempting to follow them to their origin and otherwise come to know their nature better. So, at that time, the breath was not the object of meditation.
At the time I saw the swirling lights there was actually no thought: my mind seemed to be still, and I was merely a third party spectator watching for the appearance of thoughts that might arise.
Does this alter your suggestion? As I was already attending to thoughts, were the lights a distraction? If so, do I try to forceably remove my attention from them?
Do the best you can with what you have to work with.