[FTTC] 10m extension: best arrangement?

[#1]

There's around 10m between the master socket just inside our front door and my desktop computer. It seems to be recommended that the Netgear router I've just received from Plusnet (thanks, Dave) and the BT modem that's to be installed are kept close together. So, is it best to run the 10m extension from the master socket to the desktop and install the router and modem next to each other there, or install them both next to the master socket and then run the 10m extension?
I've got power at both locations but it would be better from an aesthetics point of view to install the modem and router next to the desktop.
As an aside, I assume I can't set up the Netgear router until BT have arrived to install the modem? I'm currently using a BT 2Wire 2700HGV router.

[#2]

I had the same thought processes about what to do prior to the BT engineer turning up, and when he did, he presented a totally different solution that is working perfectly.
My 'master' socket was sited next to the front door (not a new style with a test socket). I explained that it would be great if the routers could be placed upstairs (immediately above the main socket) as this is the computer room.
His solution was to remove the existing extension cabling I had installed years ago that ran up to the PC room through the ceiling and install brand new cable and fitting the new master socket upstairs. He then (presumably using other wires in the bt cable, or by splicing downstairs) ran the signal back downstairs so that the old main socket could still be used as a telephone 'extension' for the phone.
This solution means all the cabling is neat and tidy and the master socket is sited right next to the PC. It also means that presumably, all the wiring in my house is now BT's responsability if theres ever a fault as the master socket is the last socket in the cable run

[#3]

Like Tony's had it's probably best to discuss with the engineer on the day as they can be quite flexible. Most installs are just to the master socket and no extension cabling but there are lots of alternative ways of setting things up. The engineer will bring an extension cable on the day up to 30m so I'd say from the sounds of things use that to run to where your desktop is and then put the BT modem and router together there.
You can in theory set the router up in advance, it shouldn't cause any problems but will save a couple of minutes on the day especially if you need to set up port forwarding, change the router password or any other advanced settings. If you just need to set the username and password and the wireless settings then it shouldn't take more than 5 minutes.

[#4]

Quote from: TonyC

His solution was to remove the existing extension cabling I had installed years ago that ran up to the PC room through the ceiling and install brand new cable and fitting the new master socket upstairs. He then (presumably using other wires in the bt cable, or by splicing downstairs) ran the signal back downstairs so that the old main socket could still be used as a telephone 'extension' for the phone.

This is how BT installed my ADSL line back in 2000 on the original trials. The BT pair arrives in the house at a downstairs socket, and then is passed through the other sockets on the 1-6 pair of the extension wiring to the furthest socket in the room with the computer, terminating in an ADSL faceplate. The extension wiring then passes back down the normal 2-5 pair to the other sockets on the reverse trip, but all within the one cable.
  Mike