Picture Quality and Coloring Help

Does anyone have any tips/tricks for getting good coloring and quality on icons made from caps of YouTube videos, especially videos of old TV shows?

Caps like this


where the skin tends to be a greyish/yellowish color. I use the Color Balance feature on PSP to try and fix the skin problem but a lot of the time it's guesswork.

The type of coloring I like is basic like on these icons:



But what works on some icons and pictures doesn't always work on others, so I need some new ideas, especially when it comes to making less-than-great quality caps look good. I use PSP 7 and I'd appreciate any tutorials or tips you might have. My usual routine is to use Color Balance, Brightness/Contrast, and then several layers of color like navy blue exclusion, light blue overlay, beige burn or multiply, and lights or textures.