Ideally you want to disable file/print sharing if possible and/or remove from control panel (under network), and also block it in the firewall. I am not familiar with Norton Firewall (I use Outpost) but you may want to set it up to log connection attempts to that port just so you can see if anything is going on. But 169.xxx.xxx.xxx is Microsoft's IP address when the machine can't get an IP from a DHCP server.