Sir,i have dell latitude D630 laptop, it comes with window vista,but now i have window xp but my blutooth and wifi does not working,i try some driver from net but it still no working,i have intel core 2 duo, please help me sir and sorry for my bad english

A lot of your newer computers with Vista or Windows 7 do not have driver support for XP. This means that you won't have full-functionality with XP installed. Unfortunately, there is no easy way to fix this. You may attempt to find out the exact model number of your board to attempt to install the individual drivers.
However, my recommendation is to either install back to Vista or upgrade to 7. Honestly, 7 works better than Vista and is, I think, better than XP.
Hope this helps.