I was dual booting Windows 7 and Vista for a while, and now want to get rid of VIsta. I removed from the boot option and want to format the partition that contained Vista (c: ). I tried uninstalling from cmd but it won't allow me to since it gets detected as a system partition. How can I clean format that partition?
The bootloader for Windows 7 would be on your Vista partition, therefore it can not be formatted from Windows.
You need to boot in with the Windows 7 dvd, start the install, choose Custom, disk tools and format the Vista partition, continue the install and select the Repair Windows option to restore the bootloader.