I'm sorry, couldn't get to see the post earlier. :$
And I'm all ready for trustworthy instructions.
As for the computer performance,
IE is still slow that I had to end the process manually the first time it launched.
But I don't care much about it as long as the machine's clean. Maybe it's the connection or my RAMs in need for an upgrade, but hopefully not because of some malware running its processes in the background.
No more alerts have shown up, neither of the firewalls nor from avast (except for being updated).
" thumbs.db " has vanished from the desktop.
I think everything else is ok.
And here I am, ready for today's work.