Most laptop firewire cards are unpowered meaning they can't charge the iPod. You will also have to force the iPod into firewire mode as it cannot detect it is connected without a powered port.

Also, there are many issues with Windows XP and EphPod/MacOpener. If you are getting an iPod and must use XP, get a desktop and put a Western Digital firewire card in. This is pretty-much the only firewire card that works 100% in XP with EphPod/MacOpener.