which bios are you running? This sounds like a bios issue because of the unresponsive keyboard...upgrade to 209 and use the EZflash in the bios to access a thumb drive with the bios unzipped on it.
Did you back up the OS like it asked? when I got my G73 the ASUS bloatware asked (by default) to backup the OS...this is ASUS' way of not including the Windows 7 disc. If you screwed up and ignored the prompt or turned it off you won't be able to reload windows. In safemode try to see if you can disc restore to an earlier point. Also go to the ASUS forum on the G73...https://vip.asus.com/forum/topic.aspx?board_id=3&model=G73JH&SLanguage=en-us