A day rarely goes by that I'm not asked "What editing program do you use?" I have also noticed while browsing through photo albums on Facebook that the most frequent comment made on any given photo is "What software are you using?"
As technology has improved, the world of photography has seen amazing changes! We can now take a picture with our cell phone and upload it for the world to see instantly! And, with that technology, we now have the ability to alter, enhance, and create any image that our imagination can conjure up.
So, what program should you choose? That really depends on what you're interested in using the program for. If you just want to have fun with your children's photo's and make collages or scrapbook pages, then obviously you won't want to spend hundreds of dollars for Photoshop. There are so many photo editing programs out there, literally too many to mention, but here are a few: Picasa 3, Corel, LunaPic, FotoFlexer, and Adobe.
I would recommend figuring out exactly what your needs are, doing a little research, and then experimenting with different programs. Most editing sites will give you a 30 day free trial.
So, have fun with your photographs, and make them as individual as you are!