Firefox help, it won't connect to the internet!

[Colour Bandit]

So I've used Firefox for a long time now and never had any major problems, yesterday I installed the 'newer' version and it has worked perfectly. Until now.
Clearly I have an internet connection (I'm using Safari right now, yay for having two browsers.) but Firefox keeps on coming up with a 'Unable to connect' screen. I've tried closing the browser, taken a look at the Firewall stuff, reinstalled Firefox and restarted my computer.
The Support site hasn't helped... So can you guys help?

And before you say 'Just use Safari', its really slow on my computer even slower than IE was and I prefer the look of Firefox.

Thank you.

EDIT: Also I can still change the persona and theme and doing that will load the homepage but if I click off it the 'Unable to connect' screen pops up again.

 

[Colour Bandit]

Managed to fix it now, thank you next door neighbour!

 

[AndyB]

Closed as requested.