Use Windows System Restore to restore your system to a time before you experienced the Windows Explorer crashes. If this fails, you can still perform an ASUS Factory Restore by hitting F9 at the ASUS splash screen on startup. It will use the files on the hidden ASUS partition - same as the Recovery DVD's you can make with ASUS Ai Recovery, but the restore from the HDD is much faster. See
http://www.sevenforums.com/installation-setup/150364-help-restoring-factory-settings.html for more details.
You can also decide at this time if you wish to perform a clean Windows 7 installation. You can download the Windows 7 Home Premium 64-bit w/SP1 ISO file from a link in the OP of the "Drivers. Apps, and How-to's" thread and burn it to a DVD to use for the install. Then you can install the updated drivers needed for your hardware (links for the drivers are also in that OP). The difference being no ASUS applications are installed as in the ASUS Factory Restore.
If you choose the Windows clean install, I recommend using the ABR utility from a flash drive to backup your current Windows Activation info, then after you've had time to install the latest Windows Updates and confirm everything works as it should, you can then restore your original Activation info from the flash drive. Alternatively, there is an OEM license key you can use on a tag on the bottom of your laptop.
G74SX-A1 - stock hardware - BIOS 202 - 2nd Monitor VISIO VF551XVT