Before you buy a new cell phone or new tablet, please try the following procedure to repair your device. First charge your battery, backup your important data if possible and in most cases take out SIM and SD card. It is impossible to recover your data after doing a hard reset, so online backup is always important. For all of your data, a backup should be done on an external device, hard drive, raid system or media.
Hard Reset the Samsung Ace SPH-i325
1. Remove the memory card.
2. Power off Samsung ACE, then press and hold both the left and right softkeys + press 
to power on device .
3. Release both softkeys. You will see an alert message.
4. After the alert screen appears, press the left softkey.
5. Reset begins, device will format itself.
+
to power on device .