Linux install failed - Now can't boot - Need suggestions!

Hmm, this one's new for me.
I got 90% through the install and it failed so I had to reboot. Disk 1 of the install wouldn't work to boot it up. A windows disk won't work. And not even my various rescue disks worked. I must have fubar'ed the MBR pretty bad(it used to be GRUB / dual boot'ed with Windows). I did a clean install and erased the Windows so it would only be Linux(Fedora Core 7). I'm just trying to erase the entire disk so I can start over, but I can't even get Dos floppy's to boot! What can I do??
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Snabblån edited by admin: commercial links are not permitted on the forum, thank you

Whether the hard disk MBR is messed up or not doesn't have anything to do with the fact that the floppy drive wont boot or that you cant boot from a cd.
In the case of the floppy,you either do not have it set to boot to it correctly, or the floppy drive itself is bad or the floppy boot disk you are using isn't any good.
The same pretty much applies to the cdrom not booting. You need to go into the bios and set it to boot to the floppy or the cdrom and then determine that 1 the hardware works and 2 the media is good.
Proper boot disks can be found here
www.bootdisk.com
boot iso's as well

After checking into Ferrits advice if you are still unable to format but are able to get your bootable media to work I suggest using KillDisk which should be easily found online and a trial version available. A long time ago I had issues with some versions of linux formatting a drive but a microsoft install disk would never recognize the hard drive again. Using KillDisk rectified those problems and that may still hold true for your situation.