Photoshop :: Selecting Colors/Areas Of An Image...

I have a question about selecting sections of an image to copy or edit, and the best/easiest way to do it. I've been using the Pen to draw a line around the edge of the section(s) I want to edit, than tidy up the lines, convert it to a selection, and go from there. But this can often take a very long time.
if there was a better, faster and/or easier way to do this, or if using the Pen tool is probably the best way?

I'll use

this image
as an example (for lack of a better example image). Perhaps I want to take the dark blue area of the skirt, chest and feet and edit them to a different color (maybe I want to turn them red, for instance). Obviously the image has shading so not all of the colors are exactly the same, so the Magic Wand wouldn't help much.

To edit these sections, would using the Pen tool to drag a line around the edges and convert it to a selection be the best way, or is there another better way to do this?

It may be a stupid question, but I just thought I'd ask just in case there was a simpler way for me to go about editing my images.
And if it makes any difference, I have Photoshop CS2.