How to Reset an LG Optimus
Performing a factory reset on your LG Optimus smartphone erases all data on the device and restores it to the default factory settings. A reset is critical for removing all of your personal information from the device if you plan on selling it or passing it along to a friend or family member to use. Additionally, resetting the device to the default factory settings can also resolve some software issues that can't be resolved by other means.
LG Optimus L7
Turn the LG Optimus L7 off.
Hold down both the Volume Down and Power buttons. After a few seconds, the light along the lower edge of the phone will turn on.
Hold down the Menu button in addition to the Volume Down and Power buttons immediately after the light along the bottom of the phone appears.
Remove your finger from the Power button after the LG Optimus L7 vibrates.
Hold the remaining two buttons down for an additional two seconds after the LG logo appears and then remove your fingers from those buttons. An Android icon appears on the screen for a few seconds, after which the LG icon will appear on the screen for roughly one minute. When the factory reset is complete, the phone will reboot to the initial setup screen where you can select your language.
LG Optimus L9
Tap the Menu button and then tap "System Settings."
Tap "Backup & Reset" and then tap "Factory Data Reset."
Tap "Reset Phone" and then tap "Erase Everything." The Android icon appears on the screen, followed by the LG logo. The factory reset will take roughly one minute. After the factory reset is complete, the device restarts and boots up to the initial setup screen.
LG Optimus G
Turn off the LG Optimus G and then hold down both the Volume Down and Power buttons.
Remove your fingers from the Volume Down and Power buttons after the Home, Back and Menu buttons light up and become active. A list of options appears on the screen.
Choose "Wipe Data/Factory Reset" and then press the Menu button.
Select "Yes--Delete all user data" and then press the Menu button.
Choose "Reboot System Now" and then press the Menu button. The Android image will appear on the screen followed by the LG logo. After roughly one minute, the device will restart and boot up to the initial setup screen.