Yeah, I think we have a small community here that gets on well with each other.
Anyway, yeah, this guy won't be able to see your computer as in desktop and what you are doing, as he'll be using a dos program to get data like ip address and such, but if you could simple hack, you wouldn't be able to find his. Thats all.
If you have a firewall, you should be safe from harm. If you haven't got one, get this and block any weird requests from it, like if you aren't accessing a program:
Download the firewall protection
i think hes just trying to scare you though and probably isn't even a good enough hacker to acces your files.