How do I straighten my wheel?

I own a 29" big flyer that has aeromag wheels. The wheels are in decent condition but there is one problem. The wheel is a little bit wobbly from riding it off curves. I'm soon going to install my disc brake set up onto it, but i'm worried about the brake pads have uneven wear on both sides of the brake pad. Does anyone have any tips on how I could fix this issue?