http://gimp-win.sourceforge.net/
http://prdownloads.sourceforge.net/ghostscript/
http://www.cs.wisc.edu/~ghost/
http://www.gnu.org/software/ghostview/

Unzip gtk+-2.4.10-20041001-setup.zip, then install (libraries)
Install gs814w32.exe (Ghostview - PS and EPS file support)
Install gsv46w32.exe (Ghostview [GView] GUI)
Unzip gimp-2.0.5-i586-setup.zip then install (program)
Unzip gimp-help-2-0.3-setup.zip then install (help)
Unzip gimp-gap-2.0.2-setup.zip then install (animation)

How to install: You have to download both gtk+-2.4.10-20041001-setup.zip and gimp-2.0.5-i586-setup.zip to be able to install The Gimp. Install gtk+-2.4.10-20041001-setup.exe first, gs814w32.exe and gsv46w32.exe, and then gimp-2.0.5-i586-setup.exe.

If you want help, install gimp-help-2-0.3-setup.zip.
If you want animation, install gimp-gap-2.0.2-setup.zip.

Distributing: The Gimp is released under GNU General Public License, and GTK+ libraries are released under GNU Library Public License. These licenses allow you to freely distribute the programs, including on magazine cover CDs (so please don't ask me for permission to distribute The Gimp, because you can; I'm not the author of The Gimp anyway). Be careful, to distribute both the binary and source code of The Gimp though, it's a requirement of the GPL.

The installers are compressed with 7z packer, and require around 28 MB of free space on temporary drive. They also require at least 16 MB of free memory (if you get message "Data Error" while extracting, this most likely means that you don't have enough free memory). This way the installer is 4 MB smaller.
Important: This doesn't mean that you need to install 7z. The ZIP file is standard, created with PKZIP 2.50. Inside the ZIP file, is a self-extracting 7z archive (it's packed in ZIP because some firewalls don't allow downloads of EXE files). If you can't extract the ZIP file, you probably didn't download the complete file.