That is most likely some sort of virus…
(These steps work for XP, not sure if it’s the same on Vista (or is that Win7?))
Run msconfig and check for anything suspicious at startup. You can clean anything you don’t want to start on boot there.
Also look in the start menu, there’s a ‘Startup’ menu in there. Any shortcuts placed there will be executed on startup, so some bad stuff can be hidden there too.
It really does look like someone or something is trying to hack the hell out of you… Got a firewall?
Command line host could mean someone is executing stuff through a terminal, perhaps remotely.
The net thingy one could be spam commands sent out via these terminal windows. Your machine could be used for DDOS attacks on some servers.
This is just what I think, I never actually seen such things, but with what I know, that’s probably what it would look like.
You could check ‘Show processes from all users’ to see if there’s something fishy going on as well. Make sure your account(s ) are protected by a password… though Vista/Win7 should have some basic features to block incoming connections like that… It could be something else too 