Here I will keep some notes on gimp.
Removing Image Backgrounds - GIMP Fuzzy Select
O wow! This is what I have been wanting to do for a LONG time. This is easy and works. If you cut bits out of pictures, and say use the magic wand to select, and say you fill a color or you make transparent, and you left with ugly edges. Then this is for you!
In short, with the edges selected, go Select, Grow, say 2 px. Then go Filters, Blur, Gaussian Blur. Works like a screen.
From toolbox, Select by color, select the background. Right click on the background, Layer, Transparency, Add alpha Chanel.
Rick click again on background, Edit, Clear.