How do you do pinging google? This is how I usually test if my conn is being funny. other than that, router settings (Dmz or port forward), and using a cable instead of wireless which I'm sure you do.
>ping google.com -t
Pinging google.com [74.125.228.35] with 32 bytes of data:
Reply from 74.125.228.35: bytes=32 time=19ms TTL=55
Reply from 74.125.228.35: bytes=32 time=19ms TTL=55
Reply from 74.125.228.35: bytes=32 time=19ms TTL=55
Reply from 74.125.228.35: bytes=32 time=19ms TTL=55
Reply from 74.125.228.35: bytes=32 time=19ms TTL=55
Reply from 74.125.228.35: bytes=32 time=19ms TTL=55
Reply from 74.125.228.35: bytes=32 time=19ms TTL=55
Reply from 74.125.228.35: bytes=32 time=20ms TTL=55
Reply from 74.125.228.35: bytes=32 time=20ms TTL=55
Reply from 74.125.228.35: bytes=32 time=20ms TTL=55
Reply from 74.125.228.35: bytes=32 time=17ms TTL=55
Reply from 74.125.228.35: bytes=32 time=18ms TTL=55
Reply from 74.125.228.35: bytes=32 time=23ms TTL=55
Reply from 74.125.228.35: bytes=32 time=19ms TTL=55
Reply from 74.125.228.35: bytes=32 time=19ms TTL=55
Reply from 74.125.228.35: bytes=32 time=19ms TTL=55
Reply from 74.125.228.35: bytes=32 time=20ms TTL=55
Reply from 74.125.228.35: bytes=32 time=18ms TTL=55
Reply from 74.125.228.35: bytes=32 time=18ms TTL=55
Reply from 74.125.228.35: bytes=32 time=23ms TTL=55
Reply from 74.125.228.35: bytes=32 time=18ms TTL=55
Reply from 74.125.228.35: bytes=32 time=18ms TTL=55
Ping statistics for 74.125.228.35:
Packets: Sent = 22, Received = 22, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 17ms, Maximum = 23ms, Average = 19ms