The problem has been fixed. What it entailed was not the Windows XP Firewall at all, even though disconnecting the Firewall permitted the PC to function correctly. The following was the the solution I used, so others that may run into this problem may try it and see if it helps them.
1) Got to "Start" - "Control Panel
2) Clk on "Network & Internet Connections"
3) Clk on "Network Connections"
4) Right clk on the icon for your Ethernet Card that is connected to your DSL modem - Select "Properties"
5) Clk on "Internet Protocol (TCP/IP) - Clk "Properties"
6) In the "General" tab check off "Use the following IP address"
7) Enter an internal IP address 192.168.xxx.xxx (replace the x's with a number of your choice)
8) Enter a subnet mask of 255.255.255.0 (mine automaticly entered this # once I started the entry)
9) Clk "OK"
10) Clk "OK"
How and why this worked I have no idea. This was a solution I found posted in two different sites on the Internet and there was no reason given for why it worked eather. I do know that I had that machine hooked up to DSL while working on the orginal problem. Then when I got the first issue taken care of and the owner took it back home we disconnected and removed the DSL/Lan connection and I put him back on his Dial Up Connection. That is when the problem showed its ugly head.
Anyway it worked for me and it was one of the last proposed suggested corrections I had considered. I am posting this so others that may run into this issue in the future may see if it works for them.
Thanks for the responses Jesse Bassett, jgweed and this site for exsisting

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