Packets transmitting problem and XP

I?m new on this forum so maybe I?m asking bit stupid question, but could somebody help me please? I have wireless network at home (DSL router Netgear DG824M, Apple Powerbook, 1x desktop PC and PC notebook with integrated Wi-Fi) and everything is working perfect except the PC notebook. I have no problem on wireless with powerbook and now problem with desktop pc (connect via Ethernet). Just the new pc notebook with windows xp and service pack 2 making problems. I can see available wireless network, I can connect, I have now problem (I mean windows xp doesn?t say anything). Once I surf a few pages, then it cuts out, it is still connected but it dosn’t transmit packets anymore. Can anyone help, please?