my ipad mini will not recognise wifi passwords or backup to itunes

I have tried two different routers, both of which I have reset and I have reset the network setting both times on the ipad mini. I have also upgraded to latest release 6.1.3.

Also, when I try and back up to itunes it says "itunes could not back up because an error occurred" and that's the only explanation I get. I am outside the 90 days but it has been like this since I bought it - have been too busy to sort it until now.

- any help greatly appreciated!