i am not familiar with FC but are you running SP2 on your WinXP box? i have found that the firewall on there drops pings and that sort of thing.
i think that the main thing you may want to do is make a folder and do something like this. you are going to need to have your winxp info like the computer name (you will need to put this in to your /etc/hosts file.) you will also need the share folder's name (case sensitive i believe).
in the term as root try this
mount -t smbfs -o users,rw,username="<your winxp username>",password="<the username's password>",uid=<linux username>,gid=<that username's group id>
if you need further help let me know. you can read up more on mount by typing
in the term. if you need help with your hosts file let me know that too. i will gladly help as much as i can.