HELP internal error before updating sp2

Okay here's what I did.

I have reformatted the same computer before and didn't have a single problem. But now I can't even reupgrade to service pack 2.

I tried the windows update route and the XP sp2 CD to no available. Both showed "An internal error occurred". There's no error number or whatever, just that message. It is connected to the internet now though.

I would like to reinstall every program I need but almost everything wanted that Xp service pack 2!

I looked into the device manager and here's the yellow question marked devices:
*Multimedia Audio Controller
*SM Bus Controller
*USB Device
I am not sure if those are related to my problem.

I need help!

Problem computer:
DELL Dimension 4550 Intel Pentium 4 2.40GHz
Windows XP Home Edition Version 2002 Service Pack 1