Mac OS X freezes while choosing a keyboard after reset Lion back to the Setup Assistant
Sounds like a bad install. I suggest booting the computer into the hidden Recovery partition by holding ⌘ Cmd-R at startup and doing an internet recovery system restore. It'll be the second option in the OS X Utilities window that comes up. As long as the iMac is connected to the internet it'll re-download the installer and restore a fresh system to the drive.

If you're trying to bring the MacBook back to the way it was when you purchased it I'd suggest opening the Disk Utility in recovery first and erasing the drive completely. (But only if there's no important data on it!)