Help with restoring!

A friend of mine jailbroke my phone, and I absolutely hate it. I've tried multipe time to reset all and restore it from the phone. Every time I do so, my phone stays on this black screen with a spinning wheel. It never goes away. I can't restore my phone from iTunes, because I use an Internet card and the download to update my phone before restoring, is too big. What can I do?!?!!