There's no "German" version per se. All Mac OS X installation disks are international - and English is always the default language (which can't be uninstalled, either). But on a G3/800 with 384 MB of RAM, I'd suggest Mac OS X 10.3.9 tops. If you upgrade the iBook to 640 MB RAM, Tiger would be fine for most things, but with less RAM, Tiger is much slower than Panther (10.3.x).