This sounds like a problem in your friend’s contact list or address book. To sort it out, first we need to understand where email names come from.
It sounds like your hard drive is dead. You are going to have to dig deep to get the computer going again.
There are numerous people and programs that can track your internet activities… if you are really that interesting.
It’s probably safe to say that the days of the optical drive are coming to a close. Not this week, not this year, perhaps not even this decade but I think the writing is on the wall. But not to worry.
It’s pretty scary that you are getting notifications from someone else’s account – but not scary for you!
Computers are being sold without recovery media fairly often. That can create difficulties if you run into major problems.