Nothing to do. Even if I reinstall google and rejoin my account, the problem keeps on turning on. Here's an example of an Ad that usually pops up randomly when I surf on the net... Very nasty thing.
It's ok, now. I've deleted the previous account's info and resynchronized with new settings, extensions and other stuff. It seems working and AdwCleaner doesn't find me anything dangerous but the Amazon Chrome Assistan extension (that I've already deactivated) so I have no more troubles at all. Thank for your assistance and for your time. You've been very effective to me!
Ok, there is something new here: there are no more malware detected, but it stills pops up with some Ad. I don't know why, but it seems a problem connected to Chrome itself. This is the link that appears to me: Google