I don't have any of those programs you have listed, except for IrfanView, which I think is really great. Some of the others may use proprietary formats, and if you have pictures in those formats, you may not be able to view them after you delete the program that created them. Sometimes they will use a standard format (ie. JPG) and call it something else. Irfanview can detect this, tell you about it, and offer to rename it. I suggest that you try to open any pictures you have with Irfanview, and if it works, you don't need the program that created it. IrfanView is more of a photo viewer than a photo editor, so if you want to do any tricky stuff like painting something into or out of a picture, you will need something else. If you just want to convert filetypes, or change the size of an image, or crop or flip images, Irfanview is about all you will ever need.