Drubie22,
DO NOT try to install Windows XP SP3 until all other problems have been resolved. This will not fix anything it will simply make it worse. This is a common mistake, since installing a major upgrade while a system is not operating correctly simply makes the situation worse.
As Jim stated, you'll need to make certain that the Norton AV is completely gone first. As to how to get the Internet connection to do this, first try temporarily disabling the OneCare firewall in the OneCare GUI, click Change Settings, on the Firewall tab click 'Off'. If this doesn't work, you may need to uninstall OneCare temporarily or download the Norton Removal tool on your wife's PC and place a copy on CD.
OneCareBear