no sound on laptop

Jesus Christ!

That's usually the problem with Vista laptops. If you install other OS you need the drivers. My Vista laptop needs special drivers otherwise network etc and like you said sound doesn't work. Try something like "slimdriver". It's a driver finder for your system. I think it should work with XP. It's also from Microsoft and should be free.
Jesus Christ!

Once I installed XP and didn't have a way to connect. No drivers. So I went to a local computer store and bought a "USB wifi adapter". It goes for like $50. You can find it at Fry's BestBuy Walmart etc. Once I had internet I could get all the drivers I wanted online!

The only other free alternative is if you have the original OS you could look up your driver specs for sound network etc and download the 32bit version for your XP you're installing. Once installed just take out the disc with your presaved drivers and wha la!!!