How would I do this: Delet all data on a physical drive ignore all partitions delete the entire physical drive and then replace it with a sleek, modern FAT filesystem. I mean ignore partitions as in ignore that they are there and delete everything no matter what filesystem it is.

You can use the "dd" command to wipe an entire drive by filling it with zeros. If you want to do this to the primary drive, you will need to boot to some kind of live system to perform the erase, though if you are trying to wipe a secondary drive then there's no problem.

Where DEVICE is your dev node (probably sda, sdb, etc). Please, please be careful when running a command like this, and be absolutely sure you are running it against the right device. If you accidentally run it against your primary drive, or something you want to keep, the command will likely have already done permanent damage before you realize the mistake and cancel the process.

you can use fdisk to delete partitions and create new ones. for example:
then use mkfs.vfat (for FAT filesystem). FAT is limited to files smaller than 4GB
or better use mkfs.ntfs to create a NTFS filesystem and be able to have huge files on it. I tested it with files up to 30GB, but it can go even higher.
Both FAT and NTFS are Windows filesystems, so you'll be able to access the data when plugging the disk into a Windows XP, Vista or Seven machine.
Otherwise, ext3 or ext4 are the modern Linux filesystems. XFS is a great Linux filesystem but a bit less common.

Have fun

you Have kubuntu live cd. Run kubuntu's installer and when it get's to the partition part, choose advance and then you'll manual control of all partitions, and you can then delete them. You are posting off a mac. If the computer you want to do this to is the mac, then you can use the mac install disc too, with disc utilitys in the menu bar after setting the language.

also http://www.dban.org/ of course you only need to use this if you want a forensically clean hard drive .

the FAT format is anything BUT modern
it is old ,VERY OLD , it dates to 1995
in computer terms that is 3 generations old

a fat file system WILL NOT hold a dvd iso
nor any file larger than 4 gig minus 1 bit ( 3.999...9 gig )

If you NEED a windows format use NTFS !