Here is my situation:

Windows was being loathsome, and so I finally decided to make the switch to linux.

I've burned the ubuntun distribution to a CD-R. I've gone through the installation process. I rebooted the computer, and the following message appears:

-GRUB Loading stage1.5
-GRUB loading please wait...
-ERROR 21

I've gone through the same process three times now just in case there was an anomaly at work.

The unbuntu distribution on the CD-R is intact, because I can run it off of the disc directly (like now).
I get the same message, e.g.
When I'm nearing the end of the installation phase, there's an advanced option tab which asks you how you want to boot your system. The three options are:

NONE (e.g. unclicking the boot loader option)
Partition No. 1: SCSI; 0,0,0,; SDA as EXT5
Partition No. 2: SCSI; 0,0,0; SDA as SWAP

I couldn't remember if I had accidentally altered whatever the default was, so I just clicked the NONE option. Going through each boot option would be a bit tedious, so hopefully someone on hear can help me out.

SIDE NOTE:

The partition that Windows existed on is non-functional/responsive. When I boot my system up (with no disc in the driver), I just receive an error message.

A hopeful linux user,

When you run the system from the live CD post the output of the;
(enter your password and hit <enter>)
Grub needs to be instaalled on the MBR if you want to have a dual boot system.Error 21 means that GRUB can't find the hard disk.You should format Linux partitions with the ext3 file system and if possible create three logical partitions for Linux before installing,one for / one for /home and one for swap.Try to fix Windows with the Windows CD,boot from it,press R for the Recovery Console, then at the text line prompt just type in this;fixmbr and hit enter.

I'm operational now. Thank you. XD