Why can my laptop connect to Wi-Fi signals that my iphone can't?

So i have a iphone five and i have free access to bt openzone and o2 Wi-Fi, only problem being that i can't pick up the Wi-Fi signal on my iphone to connect to them.
however my old dell inspiron | 1000 can pick up these Wi-Fi signals from the same house? What the hell! I want to use this Wi-Fi as its free, but my phone but it won't pick it up but my laptop can! Any ideas on how i can fix this?

Can I use my sim on an iPhone?

I have a blackberry ATM and I'm on contract and want to buy an iPhone, what will I have to do to make my contract sim work on my iPhone?

Phones similar to the IPhone 5?

Am thinking of selling off my Iphone4s and buying the IPhone 5… Though initially reluctant, am also considering looking into other smart phone options… Could you please suggest smart phones that are in the similar category of the IPhone 5… I shoot video extensively, so need a good camera in the phone, also the phone should be compatible with MAC OSX… I live in Mumbai, India…
All suggestions & feedback will be appreciated by heart… Thank you in advance.

Where can i buy a cheap iphone 4? - 2

My old phone died and need a new phone and want to buy an iphone 4 i'm not a millionaire so i'm on a budget and looking to spend 300$ or less. So if someone has a website where you can get cheap iphone 4's that would be great. Thank you. (Must be a legit website no B. S scams)

After getting my iphone unlocked can i use any sim?

I got my iphone unlocked ages ago and have been using tesco pay as you go ever since. But now I want to get a contract with Virgin Media. I was going to just get a sim card from them but will it work in my phone?

Removing purchased music on iTunes?

Last night, my brother synced his iPhone to my computer to download some songs as he doesn't have his own and now all his purchased music is synced to my computer & phone and I can't remove it? I have tried manually deleting them off the phone, deleting them off iTunes yet they somehow keep coming back. Does anyone know how I can fix this? I tried the Purchased playlists thinking there may have been one purchased off his phone, but no, just the usual main Purchased playlist. And now I've just noticed half of my music has also been deleted & I'm just recovering it all now.
Please any help!

Added (1). Thanks Maddy I'll give it a try, what would the folder be called? Or where to find it? Each time I try to open the iTunes folder it just opens iTunes itself

Keeping playlists when syncing iPhone with new computer?

Ok so my computer that I use to sync my iPhone songs has just died. Luckily we have an iMac which has all the music I need anyway. Although it is all the same music, it does not have any of the playlists I have made on my old computer or phone.

If I connect my phone, I'm I right in thinking that everything will be deleted, so I will only have what is on the iMac and therefore none of my playlists. Also what happens about apps?

Is there anyway to keep my playlists when I sync my phone for the first time to this iMac?