I really think you are worrying yourself needlessly, ship!
More comments inline.
Ok... one thing though - what is to stop a virus from infecting all
your
previous restore points? (not to mention the restore process
itself...)
If a person had an *actual* infection at one point in time (this is
_not_ the same thing as suspicious temp files and unopened e-mail
attachments), then using System Restore to go back to a point in time
when the infection was active would be a very bad thing to do! That is
why it is recommended to turn it off, then on again (this deletes all
the old restore points) once the infection is successfully removed. But
if you never had an infection, those points aren't necessarily
"infected." Still, it would be wise to clean house anyway (with regard
to System Restore).
I am certainly leaning toward a complete flatten plus rebuild.
It may very well not be necessary, but at least you would finally have
peace of mind.
(I remain nervous that reinstalling msWindowsXP may prove hard even
though I have a valid Product Key on the back... but shall probably
risk it anyhow!)
It depends on the method you use. If you use the hidden recovery
partition, there might not even be a need to enter a Product Key (I know
Dells work that way). If you obtain a generic OEM XP Pro installation
CD, then your Product Key from the COA sticker *will* work. If for some
reason, automatic activation over the Internet doesn't occur, simply
follow the prompts for telephone activation.
I'm sure your recovery partition is fine. I doubt very much that the
malware writers were targetting *your* particular make and model of PC!
If you're truly that paranoid, take out the hard drive and obliterate it
and purchase a new one.
(Then again, you might start worrying about
your CMOS chip being infected...
)
But seriously, stop being so nervous!