Cisco WAN :: Poor Performance And Internet Router 1800 Cable Virgin Media

Im getting really poor performance on my 1841, my intial thoughts was a duplex mismatch  however although im getting a few CRC errors (root cause unknown at this point) not enough to suggest that the this is the issue.

Heres the config:

Building configuration.Current configuration : 5274 bytesLast configuration change at 20:31:01 PCTime Sun Dec 18 2011 by admin_xversion 15.1no service padservice tcp-keepalives-inservice tcp-keepalives-outservice timestamps debug datetime msec localtime show-timezoneservice timestamps log datetime msec localtime show-timezoneservice password-encryptionservice sequence-numbers!hostname   xxxxxx!boot-start-markerboot-end-marker!!security authentication failure rate 10 log