Originally Posted by
cny-bikeman
Out of round is more difficult to resolve, as it typically involves balancing tension in multiple spokes, sometimes those opposite the ones at the out of round point. If not careful one can introduce low spots in fixing a high spot. In addition a low spot may require physically pulling the rim out.
This is a fact. If it is not significant, leave it alone. Most bike shops don't have anybody good at building wheels and a radial fix is not the best thing to start on if you've never trued a wheel before.
A mm or so is fine. It's far more likely you will make the tension uneven which will just lead to the wheel getting out of true more frequently as time passes.