While learning Python i made a small tool for windows to compress pictures better.
It s a front end GUI from various command line program

Pak_Pic050.exe : http://dl.free.fr/riOTjZJr0

Decompress it to a simple path like d:\pack_Pic050\ (user can write into this dir)
and launch PakPic.exe

It should simple enough to use
it manage Jpeg / Png and Gif format

There is some unicode partial managment, but somes errors can exist (using cp1252 and cp850)
You can report here for comments (i know free.fr download dont work fine for some users)