The approach that works best varies with the details of the footage you're working with (i.e., whether there is much red in other areas, the variation in the reds, etc.).
I often confuse the two when not looking at them, but either "Change To Color" or "Change Color" in the color correction menu work reasonably well for relatively simple color changes. Don't expect either to do the job with the default settings though ... once you select the shade of reds you want to affect, you'll need to tweak other settings and maybe even precompose and re-apply a second instance. Sometimes it also helps to first adjust the footage slightly to make the color you're trying to adjust more distinct ... maybe contrast, HSL and/or levels. For more complicated or extreme color changes I tend to use third-party AE plugins or even Photoshop.