What phone should I buy?

My Sony Xperia J is no longer working and is not worth repairing.

I now am wondering should I buy the Nokia Lumia 520 in its place. I understand this is has windows 8 and it will not be as open as to Android in terms of applications and settings etc. But in terms of design the nokia appears to be a better looking phone and the Windows OS appears to look a lot smoother (though know this will be more stripped down in terms of customisation, settings & features. And to be honest towards the end of my Xperia's life it did seem a little on the slow side though a simple wipe and factory reset probably would of fixed these issues.

Also in terms of hardware etc. the Lumia appears to have a slight advantage with 8GB internal storage and 720p video recording but I know this means nothing in regards to the camera phone as I hate the camera on the xperia J and I did try a photo with the nokia and it seemed better though using this in a phone shop its hard to really tell.

Basically I am looking for a phone that has basic modern capabilities that does not need to be a powerhouse as if I am looking for power I will turn to PC every time. As long as the phone can match or better the Xperia J for under £100 I would be happy.