How to just use Wi-Fi not monthly allowance on iPhone 5?

I got an iPhone 5, and in my contract I have 1Gb of Internet a month when am in my house I want to use the Wi-Fi only and not my allowance do I switch off mobile data or just disable 3G

Any answer would help as I'm confused

I accidentally restored my iPhone 4?

I accidentally restored my iPhone 4 and I lost all of my contacts and messages. My iPhone now has the layout of my old iPod with the wallpaper and everything. Is there a way I can get my old phone back or at least my contacts? I want my iPhone back, not my iPod. I can still make calls on it but I want the old layout back and my contacts. Is there anything I can do?

My Verbatim harddrive won't start?

I was updating my iphone via Itunes, which is on my 1tb Varbatim hardrive and Itunes crashed and shut down. I then went to reload my HD and my computer did not recognise that it is plugged in. So I plugged the hard drive into my laptop and still it is not recognised. I have tried going into "disk management" via my computer but the hard-drive is not showing to format.
When I plug the hard drive in it makes a whirling sound (or a sort of clicking sound about 10 times) then does nothing but the blue light stays on to say that It is on and has power from the computer; but yet nothing I can do on the computer to access.
Does anyone have any ideas how I can access the HD on my computer, even if to format and lose the information.
Thank you,

Added (1). Thanks CanadaRAM - I thought that maybe the answer but thought there maybe a miracle answer. The harddrive is only 2 months old off to Verbatim I go - even though I don't mind losing the information I really don't want to.

Added (2). Thanks CanadaRAM - I thought that maybe the answer but thought there maybe a miracle answer. The harddrive is only 2 months old off to Verbatim I go - even though I don't mind losing the information I really don't want to.

Self timer on camera for iPhone?

You know how on cameras, you can set a timer for 10 seconds or something, set it down, and pose for the picture? Is there an app for my iphone that I could download to have my iphone camera do that?

Tmobile sim in my iphone 4 isn't working?

Today i got a sim only contract through tmobile, i can use the internet (i don't have Wi-Fi so it's definitely the mobile internet) but i can't text or ring anyone, any ideas? The woman said it may take 24 hours but why is my internet working and not my texts/calls?

Added (1). When i try to ring someone it doesn't ring at all, it says it's calling for about 2 seconds and then beeps off and says call ended, it doesn't even ring. And when i try to text it comes up with a little red exclamation mark and says not delivered

Added (2). I just rang my new phone from my old phone and it said that calls weren't being connected

Possible to block someone by mistake on iPhone Facebook app?

I was chatting to a girl on Facebook the other Damon the Facebook for iPhone app when suddenly as I sent a message the person disappeared and the name became "Facebook user" and it was as if she deleted me.

However I text her to ask If she deleted me she said no and so I checked in my settings and blocked people and she was in there and I had to unblock her.

Now I didn't confirm any block message and didn't do anything but type a message then she disappeared!

Is there anyway I could have accidentally pressed something in the iPhone app that could have blocked her? Or was I hacked on a pc?

Dropped Iphone 4 and now it won't turn back on?

I got an iphone 4 for christmas and the other day it fell on the floor. Now it won't turn back on. It works when i plug it into the computer but when i unplug it, it only works for a minute then turns off and its fully charged.