I've Used GimpShop, and the damn thing made me angry, I was unable to actually insert a picture to edit. And I was wondering if Gimphoto + gimpad was any good. I'm unsure of it, and thought that maybe you guys could help me figure out if it was any good, if it's interface/user friendly, and if it allows for photoshop-esq editing.
And what about Photoscape, Paint.NET, photoplus from Serif, and photo pos pro? All of them are freeware, but I'm not sure which one is the best.