Sure..
Firstly, you need a windows xp sp2 cd bootable (genuine) then, next go to bios in boot configuration first boot the CDROM. Then be sure you have the CD inside loaded and when the winxp bootable cd initialize press enter, then next after loading setup follow the instructions as well. then choose and format the Drive C: only for OS of an NTFS file system and enter and you will see the windows installing setup.
You have no way to revert it back to your original system unless you have enable the sysrestore. But for sure better install fresh windows XP.
Follow the instruction bro..google is your best friend. Update us lang ok.
Goodluck.