[Gimp-user] Changing foreground pixel colors

[etchedpictures <forums gimpusers com>]

Is there a paint tool that allows me to change the color of specific foreground
pixels as I drag it over the picture while leaving the background color
untouched?

All of my photos are created using PhotoGrav which converts them to black pixels
on a white background for etching on a laser machine.

I would like to know if there is a tool similar to a brush or a pencil that will
allow me to drag it over these areas (like I am drawing) converting the black
pixels to a different chosen color while leaving the white background untouched.

-- 
etchedpictures (via www.gimpusers.com/forums)