I want to know how can I open multiple terminals on the shel using knoppix. with all other distros like debian, redhat etc ctrl + alt + f1 - 6

Check whether your /etc/inittab has some lines like these or not:

# Run gettys in standard runlevels 1:2345:respawn:/sbin/mingetty tty1 2:2345:respawn:/sbin/mingetty tty2 3:234:respawn:/sbin/mingetty tty3 4:234:respawn:/sbin/mingetty tty4 5:234:respawn:/sbin/mingetty tty5 6:234:respawn:/sbin/mingetty tty6

If you have exactly these lines then. you will have 6 terminals in runlevels 2,3,4 and only 2 terminals in runlevel 5.

Cheers, Debarshi