Sorry, I've just realised I probably posted this under the wrong topic
We were recieving normal speeds when plugged directly into the NTL cable modem. Also secured the wireless network to our household using WEP encryption. Can't see what difference changing the channel would make, there aren't any other wireless connections in the area that could interfere.
Going through the router settings, I can't see anything else that you could tweak in order to improve the connection
Here is a log if it helps:
Router Status
Account Name WGR614v4
Firmware Version V5.0_02
Internet Port
DHCP DHCP Client
IP Subnet Mask 255.255.252.0
Domain Name Server 194.168.8.100, 194.168.4.100
LAN Port
DHCP On
IP Subnet Mask 255.255.255.0
Wireless Port
Name (SSID) NETGEAR12
Region Europe
Channel 11
Mode g and b
Wireless AP On
Broadcast Name On