No they don't, "minutes" are for your phone calls and since you aren't calling someone when your using the internet (1) on your iPhone it does not use minutes.
What it does use is your Wifi's bandwith (if you are connected to one) or your 3g signal (if you have the plan for it).
(1)=If you have a call running in the background---green tab on top---then yes you are using minutes
yes, you can just use wifi access to use the Internet on your iPhone
When you use the Internet.
if you are using something that requires it then yes it does use internet
Yes I have a iPhone On tmobile and no Internet
Depending on your PC. I did it in 15minutes.
Yes, you can buy international iPhone's version (a iPhone with out Internet) in eBay or amazon, some iPhone that sell outside U.S, is international iPhone' version. You can use it with any network that you like.
no you can use the mobile network for Internet
yes .
YES
You get faster internet then the original iPhone.
If it is wifi then no it does not use your credits.
contact to people and to play and to use internet