It depends what sort of editing you want to do, but any image editor will do basic editing. If you are using Windows then you will probably have MSPAINT, in Start > All programs > Accesories > MSPAINT, but there is also Paint.net, originally intended as a free replacement to MS's Paint, and is now a tool with a lot of useful features.
It is available at Download.com as a free, no limitations, utility here;
and the developer's web site is here;
Would that do?
Paint.net needs the .NET Framework 2.0 or newer (.NET Framework 3.5 SP1 recommended), but if your Windows Updates are up to date, you will probably have that installed already.
I'm searching for a free simple-to-use photo editing program that can permit me to have just enough options on a regular consumer level. I already know how to use Photoshop, but I'd like something less professional and complex for friends and family.