some distros using grub can give grub errors when you try to re install them
for example freespire and some versions of ubuntu will do this
you can manually edit the grub file but it can be a pain
I usually store files i want to save on removable media
but before re installing the distro I use d-ban to wipe the drive.
this gives you a fresh start with a sterile drive ( no remnant grub files to mess up the installation)
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