Disk uses GRUB2, the differences between GRUB Legacy and GRUB2 also apply to the different versions of Super GRUB Disk: http://www.gnu.org/software/grub/manual/html_node/Changes-from-GRUB-Legacy.html#Changes-from-GRUB-Legacy
Perhaps the most notable difference between Super GRUB Disk based on grub legacy and Super GRUB2 Disk is that Super GRUB2 Disk does not write to the disk at all, and so cannot rewrite the MBR. Super GRUB2 Disk can only be used to boot a broken system, it cannot fix it directly. Though once a system is booted, re-installing grub is usually just a matter of running "grub-install /dev/sda".
While there are some features of Super GRUB Disk based on GRUB legacy that will never be included in Super GRUB2 Disk, the opposite is also true. For instance, Super GRUB2 Disk supports booting OSX, loop booting from iso files, booting an OS from USB without USB support in the BIOS, and other features that are not possible with GRUB legacy. Creating a Bootable Super GRUB2 Disk
To create a bootable Super GRUB2 Disk CD, simpy burn it as a disk image to a blank CD or DVD as you would any other bootable iso. Detailed instructions for burning an iso file in various operating systems can be found at https://help.ubuntu.com/community/BurningIsoHowto
The Super GRUB2 Disk image is a hybrid image and can also be dd'd directly to a drive to make a bootable drive. Using dd can be dangerous and I plan to make installation to a flash drive easier so I will not document the details here currently. The image can also be used as a bootable floppy image. Menu / Features When Super GRUB2 Disk boots it will present a menu like this: 
Many computers have buggy BIOSs that do not work properly with large drives, which usually translates to "out of disk" errors from GRUB when you try to boot from large drives without using a separate small /boot partition at the beginning of the drive. GRUB2 has native drivers for accessing drives directly, bypassing the BIOS entirely. Since it's bypassing the BIOS, limitations of your BIOS do not apply and you can access any part of any sized drive.
If you are having problems booting because of an "out of disk" error then selecting this option will likely allow you to boot. To install grub2 with ata support to fix this permanently use "grub-install --disk-module=ata".
Currently GRUB2 only supports the older PATA (also know as ATAPI or IDE) drives. If you have a newer SATA drive then this option will not work for you, but it's also less likely that you will encounter these limitations with newer BIOSs that support SATA. For more information on the limitations of buggy BIOSs with large disks see: http://tldp.org/HOWTO/Large-Disk-HOWTO-4.html .
Enable GRUB2's USB support *experimental*.
Many BIOSs do not support booting from USB, with this option you can use Super GRUB2 Disk (booted from a floppy, CD, or other media that your BIOS does support booting from) to boot an operating system from a USB drive despite your BIOSs limitation, using GRUB2's native USB drivers. This option will only allow you boot Free Operating Systems like GNU/Linux or FreeBSD, chainloading will not work with this option and so it cannot be used to boot Windows from a USB drive. This option, as stated, is still experimental.
Enable serial terminal.
This option enables GRUB2's serial console support, using the default parameters. This can often be useful for debugging as you can log error messages. If the defaults don't work for your serial hardware you'll need to configure it manually using the "serial" command as documented here:
ttp://www.gnu.org/software/grub/manual/grub.html#serial .
If you don't know what a serial console is then you may simply ignore this option.
List devices/partitions.
This option will list all of the devices and partitions that GRUB2 is able to read, with information about them like what filesystem each has. As GRUB2 uses the same module, ext2.mod, to support ext{2,3,4} any extN filesystem will be listed here as being "ext2".
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