Hello persia and welcome to Seven Forums.
Most computers come with a factory installed recovery option. The recovery option is usually located in the Start menu > All Programs and provides detailed step-by-step instructions to return your machine to the exact same condition it was in when you first bought it. That means you would have to install all Windows Updates, any programs you installed, etc.
If you provide a little more info about why you want (or need) to reset your laptop other Forum members might jump in with additional suggestions. For example, are you not able to start your computer? Do you think your computer has malware? Are you not able to get an internet connection? Are you receiving any errors? Did you recently install some software or program that has messed up your computer?
Here are a few things for you to consider:
1. Did you create recovery CDs when you bought the Acer? If not you may be able to get them directly from the manufacturer. (This is the US Acer Store so you may have to go to the store that services your country if you're not in the US.)
eRecovery Media | Acer
2. Do you think a System Restore would help your situation? This tutorial explains more:
http://www.sevenforums.com/tutorials/700-system-restore.html
3. You might find that a Repair Install will help you. If successful it will preserve your user accounts, data, programs, system drivers, etc but you would still have to reinstall all Windows Updates (probably 250+ updates which could take several hours.)
http://www.sevenforums.com/tutorials/3413-repair-install.html
Again, please provide more info about your situation and why you want to reset to factory settings.
