Keyboard & Mouse not working – even in BIOS

Hi folks. Almost suicidal with this one. Any hdelp would be appreciated. I have a Fujitsu Scaleo desktop running XP SP3. USB keyboard and mouse. Both wired. Last week, when using the computer both the keyboard and mouse froze. I waited a while to see if they would free up, but in the end I had to shut down using the power button.

Now when I switch on, the mouse and keyboard are still not working. So, I cannot get into BIOS, safe mode or anything. I have reset CMOS too but to no avail. The OS is OEM, so I don’t have an XP CD, only a “system recovery disk”. Anyway, I don’t want to lose all my files. Any ideas? Please!!!