XP hosed! Slow at RPCSS, then programs messed up

[Jessica]

My system seemingly suddenly became hosed. I can't think
of anything I installed or did differently and I've run
the virus scanner many times.

When booting it gets to RPCSS is starting and hangs for a
bit of time, then finally Windows starts very slowly.

I have no task bar and no start menu, it won't come up by
mouse or keyboard. The only way to launch program is to
go to the Computer icon on my desktop and navigate to the
executable or shortcut. Not all programs will work and
usually I'll get the error: "error using COM/OLE occurs
check installation of com on you computer". And McAfee
seems to take forever to try to load and finally gives up.

If I run disk fix (can't remember name, but it's the
Windows built in disk checker) then when it boots I seem
to have internet access and can kind of run some programs,
but I get miscellaneous errors like in Word something
about links.

I even tried reinstalling XP using the upgrade option (I
have a full installation disk). It installed, taking a
couple hours, but gave me many errors about all of the
hardware including the motherboard hardware.

Any ideas?

Pentium II-350, Windows XP, two IDE hard drives but all
software and Windows are on the master.

Thanks!

-Jessica