Well I would try to reinstall the PRESP4 Patch. I am using Windows 2000 Pro and I used the Windows Update to install SP3, and I never had a problem.
I recomend only doing the updates on Windows Update.
The part that I don't understand is Your IE and Email works, yet your FTP or Windows Media Player don't. If your Internet Explorer works (and goes to pages) then you have the Internet and a Valid connection, so the problem would be something maybe with a Firewall. Some Firewalls block FTP and Prevent certian Streaming from the net.
If you don't have a firewall installed (and are not using a Router presuming you have Cable or DSL connection), then something happened during the setup process and I am sorry, but the only solution I can think of is to reload your PC.
I am running Windows 2000 Pro SP3 for now, and thats kind of the flaw, is installing a PRE SP means that it can contain bugs. You can wait and see if when SP4 is released if they fix it, You can contact Microsoft and see if they have a solution for you, but the best thing I believe would be to format.
Good Luck
