You can try and blow away the hard disk and start from scratch following exactly what the prompts ask for, as they give pretty clean instructions from the beginning to end. I suppose you might have tried to install with nothing attached to the computer, and with all the bios configured to boot from the CD etc etc... Fixing stuff from the command line is too nasty to begin with.
There are plenty of wipe disk options out there, consider these two below, by Darik,
or disk wipe,
that will clean your hard drive out!