My iphone isn't working properly?

My friend gave me her old Iphone and I knew things were wrong with it but how much would it cost to fix it? The buttons for the volume don't work, the mic doesn't work when I'm on a phone call but it works any other time and the lock button has been pushed in.

Blackberry 9360 or iphone 3G?

Ok so I have a blacberry 9360 and I do love my phone but there always to be something wrong like now my battery is really dodgy because when I'm on the net my phone says battery is low shutting handheld down and my battery is half full its so weird, so I have to have the charger left charging it even though it says full. I know its the battery not the phone but all my friends are coming off blackbery going on iphones and to be honest even though its just my best friend who's keeping his blackberry I won't be able to talk to all my mates accept him and iphone seems so good like everyone says how good they are. But my dad says we can swap phones because he said he's getting old now and he don't mind just having a normal phone like mine. His phone is in pretty good condition and yeah its an old iphone because its 3G, I feel abit guilty because I do love this phone but its annoying me now and I'm not sure what my mum will say or what I should say I feel so ungrateful but I've always told her how much I loved and apreciated this phone before I was even interested in iphones, but mum said that iphones were meant to be the best phones so surely she should be ok right. I dunno am I making a right decision? I do want my dads iphone. And will his sim card work in my phone?

I don't want my iPhone to say Verizon?

On a lot of Verizon iPhones, it just says your bars and 3G, well mine says Verizon and I don't want it to. Is there any way to get rid of it without a jailbreak?

Jailbroken Iphone won't stop rebooting?

Just jailbroke my iphone, i don't want to hear anything saying i shouldnt have done it.
I used the same website my friend had used and hers was fine.
I went to go and try to change the backgrounds and my phone will not stop rebooting.
all it is is the screen with the apple on it and its all black, and it will not stop.
anyway to stop this or do I have to go buy another phone?

How to restore jailbroken iphone 4S?

I can't seem to open cydia. The moment i open it, it goes back to main page. I'm not able to restore in it anyway or reinstall it.

Tried using erase setting and content but it seems useless. I'm quite slow in this so a detailed explaination would be preferred. If you don't mind, maybe you can leave me your email and guide me along.

Thanks a million to those who can help. I have been stuck in this situation for months. :'