1. Try Knoppix (live Linux boot from CDROM) and use K3B to burn the important files on DVD/CD
2. Would you mind share your story in the disussion "我的 NB OS 自毀了, 電腦公司要我復原"
3. Your computer may accumulate too much dust on heat sink; the local overheat cause som unpredictable problem. Please check CPU, VGA, HDD, RAM and PSU.
4. The electric connections may have some rust spots, spray some WD40 on HDD cable socket, RAM socket and AGP or PCI-X socket. P.S. always use tissue paper to wipe excess WD40 to avoid dust accumulation.
5. The worst possibility is the contacts between HDD casing (head amplifer) and HDD PCB (cache and decoder) get rusted. In this case, you will need Trox bit (hexgonal star bit, cellphone screw bit) to open the HDD PCB. Of course, spray some WD40, wait for few minutes, and wipe the excess oil clean.
6. You probably need to re-install OS from the bottom up. Win 2000 SP4 international version is a good choice, if you don't play too much game.