The safest, most secure, and entirely legal method is to download an official Windows Vista ISO and convert it into a QCOW2 image yourself. Prerequisites A Linux host machine (Ubuntu, Debian, Fedora, or Arch). QEMU/KVM and Virt-Manager installed. An official Windows Vista ISO file.
qemu-img convert -f vpc -O qcow2 windows_vista.vhd windows_vista.qcow2 Use code with caution. 3. Recommended QEMU Setup for Windows Vista Windows Vista Qcow2 Download