Samsung Galaxy S I9000 Hard reset solution here
Note: Please back up all of your personal data before you proceed. All data will be deleted on your Samsung I9000 Galaxy S by doing this procedure. However, this process will NOT delete data stored on the microSD memory card.
To Hard Reset Samsung I9000 Galaxy S
1. Turn the power off. If your Samsung Galaxy S is frozen, pull the battery out and reinsert it
2. Hold the Volume Down button
3. Press and release the Power button
4. You are now presented with a menu that allows for Fastbook, Recovery, Clear Storage, and Simlock
5. Select Clear Storage by pressing the Volume Down button
6. Press and release the Power button
7. Now simply confirm your decision: Volume Up for YES and Volume Down for NO
If YES is selected, all data including third-party applications will be deleted from your Samsung I9000 Galaxy S. Once the wipe is complete, the phone will reboot to its factory fresh state.