Can't load Knoppix 5.0.1 LiveCD or DVD on Acer laptop

Hello, very new to Linux here

I want to run Knoppix on an Acer eMachine E520-2496 laptop because the installed Linpus Linux is command line only and I'm not remotely competent. I'm using a known good live CD but after it scans for USB/Firewire devices I get the following:

Can't find Knoppix filesystem, sorry.
Dropping you to a (very limited) shell.
Press reset button to quit.

Additional builtin commands available:
cat mount umount
insmod rmmod lsmod

knoppix#

The CD runs on my Dell tower running win XP so I know the disk is good. The laptop has a 160GB SATA HD in two 80GB partitions. I changed the mode to IDE in the BIOS after the CD 'failed' under the default HD mode. That made no difference, although it did remove all the boot errors when I let Linpus load from the HD.

Can anyone suggest what may be stopping my live CD from loading on this laptop? I have 1GB of RAM so I don't believe memory is an issue. I want to give the computer to my son for his birthday on March 10 but he is also a hampered windows user so I need a GUI system.

Thanks for any help,
Tony