Q: Is there a way to install that does not use so much space?
A: There is the "Poor Mans Install", where you can copy some files from the CD to the harddisk. It will run like from CD, but the CDROM is free for other use and its a bit faster. Although you'll need a bootfloppy or change the Bios options to boot first the hard disk with Knoppix (i.e. the second hard disk or d: unit).