How do I format my HD once Ubuntu is on it?

You will need a bootable CD or USB to start the installation. Part of the install process is partitioning so you can delete the current install (This will destroy ALL data so be sure your backups are up to date) and then install to the new freed space.

You don't need DOS or anything like that, it's already built in.

TNX for your help. Unfortunately the problem remains.

I have burned a DVD-R with Ubuntu 12.?? I have confirmed that BIOS is configured to boot 1st from DVD/CD drive and then from HD. I have placed the DVD w/ Ubuntu 12.?? into the DVD/CD drive, started the computer, and the old Ubuntu 11.?? loads. This old Ubuntu shows the DVD/CD drive containing the Ubuntu 12.?? program.

I believe there is a corrupted file on the HD and wish to erase the HD; then begin anew with the DVD of Ubuntu 12.?? Alternatively, how do I force the downloading of the DVD once Ubuntu 11.?? has opened?

Again, thank you, jeff

How did you burn the CD?

I was about to post this note (you're comment vis a vis how the CD was burned is spot on).

Initial DVD was burned using a program on my Windows 7 machine. Second CD was burned using the Nero packaged in the Ubuntu 12.?? download. The latter is currently loading; hopefully with success.

My question regarding how to format the HD remains open. Using MS-DOS or CMD one can get to the C: prompt and use the command 'format C' to reformat the HD. Can this be accomplished with Ubuntu? If so, how.

Thank you,
jeff

The Ubuntu liveCD has gparted which you can use to format partitions with

There is no C: in Linux, that is a Windows construct

Okay, Windows construct and all. . . Still, is there any way to reformat the HD on the machine running Ubuntu? I understand such an action would delete all data leaving only BIOS to run the machine. Maybe the other way to ask this same question: How would one overwrite the HD as to delete all data on it?

As explained earlier, you have that option in the installtion process. You will be asked what to do with the hard disk.
Your main focus should be on getting the live CD/DVD with the installer running. You will need it anyway.

Also: You should not format a drive while the OS on it is running, not on Linux and not on Window. Never!

TNX. Let me re-phrase - once the computer is started, it automatically boots to Ubuntu. How does one avoid the boot to Ubuntu? In the case of Windows, one can go to RUN > CMD and then using CD command get to the C prompt, whereupon the format command is given.

The objective is to 'shred' all data on the HD.

Any thoughts?

Again, thank you all,
jeff

No, the process you are describing is wrong in two ways.

1. You are formatting a disk from which the currently running OS (including the format tool) is loaded from. You are sawing on the branch you are sitting on.
2. Formatting a hard drive does not delete it's content. It's like removing all road from a city leaving the building intact. It will make them harder to access only.

How to get it done the right way.
1. Step one create a working Ubuntu live CD/DVD: https://help.ubuntu.com/community/BootFromCD
2. Boot from that CD/DVD
3. (optional) Find out the device name (the first HDD in system is usually /dev/sda and run 'shred devicename'. It will wipe all data on the disk safely but might take a lot of time.
4. Run the installer!

Everything else is straight forward.

1. gksudo gedit /etc/grub
2. change GRUB_HIDDEN_TIMEOUT to something higher than 0 (in seconds) and save the file.
3: sudo update-grub

oops lol not in seconds but higher than 0 so 1 :p

That won't help when booting from CD.

Thomas: Yep sorry, this was just about his question how to avoid to boot automatically into ubuntu.

Jeff: You can also boot from USB: https://help.ubuntu.com/community/Installation/FromUSBStick
And with windows: http://www.linuxliveusb.com/