Xbox Live set up question - LAN/proxy connection

[gaz@manc]

I've just moved into a new flat which has internet already included - I'm not technically minded so bear with me! How do I set up Live if I've had to go to internet options and "use a proxy server for your LAN" option??

EDIT:

I've been fiddling around with Live - if I can find the subnet mask, gateway and dns servers I imight be able to set it up. Anyone know where I can get these?