I'm using a Windows XP 64-bit OS.  I have SW running fine, but since SP1 (which was installed originally from the disk) I haven't been able to actually install the service packs.  It hangs at:

Never installs.  Been sitting all day.  I've tried going into the files and finding the update file that was downloaded and running that, but it goes to the same screen and hangs the same way.

Any help?