Since you haven't said, have you tried turning your phone off, pull battery out, then put it back in and restart the phone yet? Lets try the simple things first.
Click on this link (if it doesn't work go back to page 2 for my post with the same link in it and click that one). This will completely restore your phone like you just got it out of the box at the store. Don't worry about contacts or applications you have on your phone, they will redownload via your google account. Do you remember your google account name and password?