Change keyboard

Hello,

I have recently acquired a Lenovo Thinkpad T43 running windows XP SP3. The machine came without installation disks and, generally, it is fine. I do however have one issue, I work with a UK keyboard and control panel regional settings will not allow me to change from the US keyboard which has a different layout. Is there any way I can change this setting (without the original disks)or do I need to format the drive and re-install my own copy of XP SP3 for which I do have disks, and is it as easy as that?