This black screen appears because you deleted Ubuntu without deleting grub, so when you restart your PC, it hangs on grub since there is no Operating System (OS) to start.
To fix this :
First, you should use a tool or a software to make a USB drive bootable (I suggest Universal USB installer if you are running on Windows or GParted if you are using Linux).
Then, plug your USB drive to the PC and restart it. Then, before the grub appears, press the button that opens the BIOS settings. After that, go to boot section and put the USB drive in the top of boot list. Then, save and exit.
After restarting this time, it should boot on the USB drive and you can install Windows XP on your PC.