Ubuntu – Configuring network to set wlan0 as primary

I recently had to rebuild my pc and decided to go for ubuntu 14.04. I think the mistake I made was I started from a 12.04 install disk instead of the 12.10 disk I'd used previously and when given the option set my primary connection as ethernet (because the wireless option didn't work).

After upgrading to 14.04 etc, I managed to get the wireless working, or more using steps like ifconfig -a and the likes I managed to prove that the wireless card etc. is all installed and working.

However every time I boot without a hard wired connection plugged in I get the message "waiting for network configuration".

I can then once it's booted without a network get my wirless working using

sudo ifconfig wlan0 up
iwlist wlan0 scan

This seems to kick the wireless module into life and it appears in the GUI and I can then select a network, however all the options like edit network and disconnect etc are all greyed out.

What I would like of course is if the WLAN0 was just set as my primary default network so I've been looking for a solution to this and it would seem that I need to adjust the old /etc/network/interfaces file but when I try to do so using the

sudo vi /etc/network/interfaces

command I, well I simply have no idea what I'm doing. Other than that typing :q! gets me out of there before I do to much damage!

As far as I can tell (by navigating to the file in the GUI) the output of my /etc/network/interfaces is as follows:
(obviously not including the " in each line that's just to break the heading rule of the #)

"# This file describes the network interfaces available on your system
"# and how to activate them. For more information, see interfaces(5).

"# The loopback network interface
auto lo
iface lo inet loopback

"# The primary network interface
auto eth0
iface eth0 inet dhcp

If this is the case then this clearly doesn't contain what it should do but I don't how to fix it. Nor do I even know if I'm on the right track.

Any help would be appreciated thanks 🙂