No operating system will overwrite itself.
Just boot from your factory reset disks and you will be fine. Most likely there's no need to run DBAN (free download) first, but that won't harm either.
I've seen it discussed that you need to work inside Windows 8 to reformat a drive, instead of the old-fashioned F8 on startup.
Well, I did that, but it reinstalled the same Windows 8 Release Preview and just wiped everything else from the drive. I was looking to get my computer back into the Windows Vista my computer came with and then reinstalling Windows 7.
When it didn't erase Windows 8 completely, obviously it didn't erase a lot of the problems I was having, either.
I can't connect to the internet. Either with wifi or with an ethernet cord. It won't work. When I go into troubleshoot, it tells me the troubleshoot has failed. There is no sound. When I try to troubleshoot the lack of sound, the troubleshoot fails.
Basically everything is failing. I would like to completely, 100% wipe my drive and start over with the operating system waiting in BIOS. How do I access that, since Windows 8 won't let me do it from boot up.