Well this will give you ideas on getting only the eyes. Then you just need to play around with image settings (brightness, contrast, saturation, color, etc) on individual parts. If you don't like the sharp look (like if you dont select the lasso COMPLETELY right), just use the blur option and do a small blur around the eyes. Using the burn tool right near the eyeline also works to make it not look photoshopped.
You may also want to search google for fire images or whatever and then use that as a layer to blend into the eyes...
