[Zyonin]

Any image editor (EXCEPT MS Paint) will work with .tga just fine. It's one of the base formats I use since it does not have the "noise" issue that jpegs do. Free image editors include:

Paint.NET: Simple interface like that of MS Paint (of which it is based on) however it's more extensive and powerful than MS Paint. It does needs the .Net runtimes however most modern Windows installs have this.

The Gimp: This cross platform (Windows, OS X, Linux, Unix based OSes) image editor has some quirks but it's quite powerful once you get used to it. It's pretty close to Photoshop in it's capabilities however the GTK 2 (toolkit also used for the GNOME Desktop Environment for *nix OSes) based UI (including dialogs) and floating windows is a large departure from the Windows UI and widgits. The Gimp is quite happy to work with .tga as well as Photoshop formats. I use The Gimp quite regularly.

Just about every commercial image editor will work with .tga. A good commerical image editor is Corel's Paintshop Pro. I personnaly used the old Jasc version (v7) for many years before converting to Linux). The only thing the old v7 had problems with was Photoshop images.

To simply view .tga the already mentioned XnView and IrfranView work very nicely for this.