I don't know elements very well... but maybe you can tell me if you can do this, or not...
when you go to adjust the hue/saturation... are you able to choose reds/blues/greens/yellows/magentas there? so that you're only modifyng those?
What I tend to do is up the saturation on all colours a bit, then bring it down in the reds and yellows a little.
Photoshop Proper has the ability to constrain each colour choice as well, so that you're only tooling around with the yellows in the skin tones, and leaving the pretty flowers alone.
Another tool I like for this is "selective colour" which I guess may not be available in Elements.... it allows you to control the CMYK levels in each colour band... which is a good way of adding colour richness, without using the saturation control.