I've tried to upgrade from 12.10 to 13.04 but it failed and result in "unstable system" or something.
sudo apt-get install -f doesn't work
sudo do-release-upgrade says I'm up to date.
So I though of deleting my current unstable 13.04 Ubuntu and install it fresh new(if there isn't something else i can do), but the problem is that I have dual boot with windows.
how can I delete my Ubuntu and install it fresh new, without touching windows?