Chris,
Your 12" Powerbook will not run Mac OS 9, which the Norton CD uses. (Of course, you can still run earlier programs in Classic mode under OS X.)
*Try restarting your computer and immediately hold down 'command s' (the command key is the Apple key; hold it like a shift key).
You will see lots of text that is usually hidden.
*When it's done, type
fsck -y (and then press the return key)
This is the FileSystemCheck program. It should fix the problems on your hard drive.
*You may have to run it twice or more times. If the last message is "The filesystem was modified", type fsck -y again and press 'return'. Continue until it says, "The filesystem appears to be ok."
* Type 'reboot' and press 'return' to reboot into OS X.
*** WARNING: Use this or any disk repair program at your own risk. Even though it's rare, you could lose data.
(I apologize if any of this was too elementary.)
Doug