how to factory reset settings on macbook

When you want to reset to factory settings, could you explain why you want to do that? For example, you want to sell it so you want to remove all personal information? Or for performance purpsoes? or ?

For performance purposes, have you look at this FAQ on tuning OS X performance?

If reloading the system is meant to address disk fragmentation, you can use a tool like iDefrag.

Some would recommend this sort of action isn't needed, however, if you want to rebuild your system from scratch ....

1. Ensure anything you want to save on your hard drive is backed up, as you'll erase the hard drive
2. Find your OS X 10.6 DVD, and reboot the system
3. Answer what language you want to use
4. Before proceeding with the installation, from Utlities on the menu bar, bring up Disk Utlity, and do a secure erase of the hard drive, where you write zero's to the drive. The hard drive will now be empty and as clean as can be
5. Proceed with the OS X installation
6. Do several Software Updates to get the system back to 10.6.8
7. From your original OS X disk (2nd one, Applications), install the iLife applications
8. Install any other applications you use
9. Do several System Updates, until no more are needed
10. Restore any data you want toDan your hard drive.

You should update your system in your profile, as it says OS X 10.6.8. For Mountain Lion, reboot holding the command and r keys down, to enter recovery mode. Bring up Disk Utility and do step 4 above. When that's done, for step 5 above, on the recovery menu, choose to reload Mountain Lion (unless you created a ML boot disk). This will take some time.

This procedure does wipe your disk clean, so if you have programs like iDvd, which is not available for download from Apple, and no OS X DVDs that came with your system to reload, you'll lose them. If you've downloaded programs like iPhoto from the Apple App Store, you can download them again without charge.