RescueCD - what is this for?

[Timothy Murphy]

David Timms wrote:

>> so I burned a Fedora-7 rescueCD and tried that,
>> but it seems I was then supposed to insert the system DVD.
>> 
>> Actually, this machine didn't have a DVD reader, so that was out.
>> But it left me wondering what the purpose of the Rescue CD is?
> The rescue CD has the boot loader, and the stage2 installer taking only
> about 100MB.
> The disk is actually multiuse:
> - use it to start an install from network or hard disk
> - use it to fix a broken system.
> It uses the same kernel / boot that the dvd-iso would use to boot your
> system, and hence your system can be trashed but you can still get
> access to it to make fixes.

That's what I assumed would happen.
However, when I put the Fedora-7 Rescue CD in,
I was given a number of choices, the only relevant one being (IIRC)
"Repair system".
When I chose this, I was asked where my DVD was to be found -
CD, hard disk, etc.

I only tried this for a minute, and may have missed something,
as I intended anyway to get out my trusty Knoppix CD.

But if you have an F-7 Rescue CD,
could you put it in and tell me which option I should have chosen?