If I had to guess, I'd say your hidden ASUS Factory Recovery partition is corrupted in some fashion, so that F9 just gives you the option to boot from DISK 1 of the Recovery DVD's.
If you've spammed that F9 key at the ASUS splash screen on several restarts and can't get different results, you may need to choose that option, OR use some partitioning software to securely wipe the drive, then perform a clean Windows 7 installation, as discussed in
http://www.overclock.net/t/1156654/seans-windows-7-install-optimization-guide-for-ssds-hdds or elsewhere in this forum.
G74SX-A1 - stock hardware - BIOS 202 - 2nd Monitor VISIO VF551XVT