Are you experiencing any packet loss? This is what it should look like when you ping a site such as google.com:
bash-2.05b$ ping www.google.com
PING www.l.google.com (18.104.22.168) 56(84) bytes of data.
64 bytes from 22.214.171.124: icmp_seq=1 ttl=242 time=61.7 ms
64 bytes from 126.96.36.199: icmp_seq=2 ttl=242 time=57.9 ms
64 bytes from 188.8.131.52: icmp_seq=3 ttl=242 time=54.7 ms
64 bytes from 184.108.40.206: icmp_seq=4 ttl=242 time=51.2 ms
--- www.l.google.com ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3028ms
rtt min/avg/max/mdev = 51.235/56.413/61.748/3.880 ms
Notice the 0% packet loss, i'm running Linux so in windows this probably looks a little different but thats the main idea.
I would suggest you get a packet sniffer such as ethereal, and see what's going on with those packets. To me it sounds like your routers firewall is your culprit.