Without having to mess with Photoshop, you can correct your photos via the Improve Your Images website. Over on GeekSugar, they tried the site for themselves, with mixed results. One was not noticeably improved; however, the second was drastically improved. Like they said, what do you have to loose with a free site? It could resurrect some of the photos you cursed when you saw how they turned out because they looked nothing like you expected them to, leading to vacation photos that are as vivid as your memories.