I'm afraid I have this problem too - about 21 seconds lost between your Load@7 and Load@8 sections. No firewalls in use at all.
I need to do some more tests before posting any logs though (and can't get on the server just now). I want to see if a wired connection is any better than wifi too.
Mine was doing it on both wired and wireless
I find Windows 7 firewall just does what it wants
Windows 8 is even more crazy
Turned off local firewall on server takes about 5 seconds now(normal)