I'm a happy Knoppix newbie, but I think that the boot time can be improved.
I boot Knoppix from its .ISO image file in a folder of an USB flash disk with Grub4dos.
This is the Knoppix entry in menu.lst:

title Knoppix 7.2 Lnx 32b (fom ISO)
find --set-root /iso/ADRIANE-KNOPPIX_V7.2.0CD-2013-06-16-EN.iso
map --heads=0 --sectors-per-track=0 /iso/ADRIANE-KNOPPIX_V7.2.0CD-2013-06-16-EN.iso (0xff)
map --hook
root (0xff)
kernel /boot/isolinux/linux ramdisk_size=100000 init=/etc/init apm=power-off nodma vga=normal nomce lang=es keyboard=es xkeyboard=es BOOT_IMAGE=knoppix bootfrom=/.//iso/ADRIANE-KNOPPIX_V7.2.0CD-2013-06-16-EN.iso noprompt
initrd /boot/isolinux/minirt.gz

Knoppix boots well, and it does it faster than Windows, but, while booting, it stops for several seconds sarching for Knoppix filesystem, showing this message:
"Cannot find Knoppix dir in ISO file /.//iso/ADRIANE-KNOPPIX_V7.2.0CD-2013-06-16-EN.iso"
It obviously refers to the bootfrom= param in the kernel line.
It tries several times all the drives and partitions until it finally boots saying something like: found ISO in /dev/sdb1/mnt-iso/iso/ADRIANE-KNOPPIX_...
After adding the param nodma to the kernel line, it booted fine the first time, bot not always does it.
If I just change the bootfrom= param to /iso/ADRIANE-KNOPPIX_... (instead of /.//iso/ADRIANE-KNOPPIX_...), it gets worse.
I hope this issue can be improved soon.
Best regards.