you can do from within Windows with their software or this way when booting-up.
1
Consider what data you still need from your Acer Aspire One's hard drive. Save the files to an external USB device.
2
Restart the Acer Aspire One's operating system. Wait for the Acer logo to appear on the LCD screen.
3
Press the "Alt-F10" keys at the same time to bring up the recovery menu. Press "Enter."
4
Click "Next." Follow the prompts that appear on the screen to restore the operating system back to factory settings.
5
Use the drop-down boxes to select the time zone and language information for your Acer Aspire One. Restart the netbook when you are prompted to finish restoring the computer.
6
Connect the external USB device to...