da, it would help if you would tell us exactly what your phone is, or isn't, doing. I would start with a
soft reset. Simply pull the battery out, after a few minutes put it back in and power up your phone.
If that does not work, consider a hard reset and a new battery. This '''will remove all your data''':
Turn your phone off.
With the phone off, press and hold the Volume Up key and the Home key, then press and hold the Power key. You'll see the Android recovery screen.
Scroll to Wipe Data/Factory Reset using the Volume Up or Down keys. Select with the power key.
Scroll down to Yes, Delete User Data and select it.
Back on the first screen, scroll down to Wipe Cache Partition and select it.
Your factory reset is now complete.
Go to Reboot System
Now to restart the phone.