Looking outside the well known Graphix apps has anyone had a play with Photofiltre ? It is reputedly very powerful and well featured but also free. I used it a few years ago and it had all the capabilities of Photoshop at the time. Find it on www.snapfiles.com in the Free Section under the Graphics and Photo Heading, Image processing.
I don't have Power Shop. I do have GIMP but don't use it.
For cropping screen prints, I use Windows Paint. And for resizing, I use IrfanView. I also have the software that came with my Canon 450D and Panasonic TZ10 but don't use them either.
You mentioned yr two sons. Why not just buy a student version of PS for $179. That's what I just did, and for the learning curve, I've ordered a book from amazon for $50. That way, you can have the industry standard at a reasonable price.