wildtrekker:
Hello and welcome to the forums. If you would please fill out your system specs in your forum profile that will helps us better provide some useful information.
Is this machine wired or wireless, do you have the latest driver for the network adapter installed from the adapter manufacturer's website, or failing that at least from the PC manufacturer's website.
When you reboot the PC and your XP machines are not showing up, can you still get on the internet, can you still ping the other machines by ip address and or netbios name, before you go through the disable enable routine. While the computer is not showing the other machine can you do an ipconfig /all to make sure that it is getting DHCP information?
Please provide if possible the Manufacturer, model name, model number, version number information for your network adapter.