I have long recognized that to be usable by young kids, xjig really needs a better user interface. So I wrote a launcher, xjig-menu to address the problem. It adds a file open dialog (via zentiy) and support for more file formats (via imagemagick).
Update
I have put this script in subversion and added a man page. Check it out:
$ svn co svn://svn.debian.org/pkg-games/people/synrg/xjig