Only because you said "as many different answers as possible", I still use Photofiltre. Way, way back when I was looking for my first free editing program (besides MS Paint), there was irfanview, but Photofiltre had an easier learning curve (although irfanview does more stuff. And not that irfanview is hard, either.) Photofiltre does all the regular stuff, plus batching, drawing lines and arrows (not curves), text, smudge, paint, etc. Very intuitive. Last I checked (10 years ago?) the English version still only had French instructions, but I have never needed them.
A good free program, but I'm guess not anything better than others.
