Boot the ISO and attach your new QCOW2 disk to install the OS from scratch. How to Run Your Windows XP QCOW2 File
The QCOW2 file format is perfect for this. It is the native disk image format for QEMU and KVM. Windows Xp-qcow2 Download
Downloading a pre-made image is fast, but making your own is safer. It ensures no malware is hidden in the OS. Step 1: Download a Windows XP ISO Boot the ISO and attach your new QCOW2