It is called Windows Messenger. That's what it's labeled as under "Services". The IM program is MSN Messenger. I'd always get porn spam on Windows Messenger when I was playing a game online. I disabled it and I haven't had trouble with it since.

EDIT: Actually, you're right. Never mind me and my forgetfulness.

I use Sygate Personal Firewall. Doesn't slow me down. I usually get 200k/s speed dl with it on.