So far I have tried many different programs but my favorites are Picasa which is a good basic editor, but it is just a basic editor, just google it to get the download. Go to http://www.picasa.google.com/
the second picture was done on picasa.
Next in line is picnik at http://www.picnik.com/ for download. you can get there from Picasa but I find it is more convenient to go through picnik after saving in picasa if you used it. Picnik is a really fun program that does not take up computer memory as it stays on the Internet and the free version shows all the steps you took on the last 5 edits you do. They also have a pay for service which adds to the basic program including keeping track of all your editing steps for all the photos that you edit. These next pictures were done in picnik.
Layered with star background
Next is Photoscape which can easily be downloaded from http://www.cnet.com/. I usually go through them as they check for virus, etc. and the download is easy. This program has a little more finesse to it, especially when it comes to tweaking your colors and they do it on two different levels of skill. Plus cnet has lots of other programs to try free, free to try, and purchase. This next picture was done in photoscape.
Color adjusted, selected Region out of focus- pixelated
Region out of focus- zoom
The last program to get is gimp which I also downloaded from http://www.cnet.com/ This is the only website I would recommend downloading gimp from there are many listings for downloaded gimp and I tried a couple and had some really horrid experiences until I found it on cnet. Then I had no problem. This is the closest free program I have found to photoshop. There are also plug-ins like photoshop available for it. It is however the hardest of the different programs that I have recommended and I am still learning about it. There are you-tube instructions available and also books. see amazon though my website for gimp books. Search Amazon.com for gimp books. I use it for all kinds of more complicated operations like removing power lines. I did not edit with gimp this time due to time constraints. Between these programs I find that I can do pretty much all the editing that I want to do.
I hope you will try some of these programs you have nothing to lose and a lot of fun and learning to gain