You can use PaintShop Pro 9, it does many things that Photoshop does, newer versions of PaintShop are by Corel and you know what happens with things that falls in the hand of Corel. If you can find somewhere the old PaintShop Pro 5, it does all the basic manipulations you need for an images, is very fast, runs verywhere and is portable (no installation needed).

Stupidity also evolves!