May I offer an alternative? I know maybe this isn't what you are looking for, but for beginners in the subject I always think the best program for editing images is Paint.NET, you should try it, is like a photoshop but is less sotisficated.
This should introduce you to the world of advanced editors but it will be easier than any other program you use, off course, it's not comparable to a Photoshop but it should be enough to begin... Best of all, IT'S FREE!
You should try it:
www.paint.net