你的本本改XP比較簡單, 步驟如下

1. HP OEM XP 光盤
可以從國內網上下.
也可以找個零售版XP, 自己加HP OEMBIOS的四個文件.
使用HP OEM XP的好處是無須激活, 無須輸入注冊碼. 可以自動下微軟更新, 無須破解. HP OEM XP的激活過程其實就是讀一下BIOS, 找"Hewlett-Packard"這個字符串. 你的本本的BIOS應該已有這個字符串.
如國你已經有正版零售XP, 直接到下一步即可.

2. Slipstream drivers into your XP CD using nLite
The previous post has already listed the steps of the process. It's not that hard.
I already found the chipset/video driver for you.
http://downloadcenter.intel.com/filter_results.aspx?strTypes=all&ProductID=2991&OSFullName=Windows*+XP+Home+Edition&lang=eng&strOSs=45&submit=Go%21

Use winrar to open the exe files and extract the drivers.

Recommendation: Google and see if somebody else has already downgraded to XP and posted the other drivers. HD Audio driver could be tricky to install.

Other thoughts:
Before you do anything, first create the recovery discs in Vista. In case anything goes wrong, you can restore to Vista at least.
Instead of completely removing Vista, you can also set up XP/Vista dual-boot. A good article for XP Vista dual-boot can be found here:
http://apcmag.com/how_to_dual_boot_vista_and_xp_with_vista_installed_first__the_stepbystep_guide.htm

Have fun!