Help really needed: Formatted / partition by accident.

[nick lidakis <nlidakis@verizon.net>]

I was having trouble with my monowall  router running off a compact 
flash. I decide to reinstall the monowall boot image onto the CF card. 
In the process I must have mistyped and accidentally wrote the image to 
my boot partition i.e. /dev/sda1. The machine now boots into monowall 
instead of Grub.

Using Google, I can only find articles or HOWTO's on recovering a 
corrupt or overwritten master boot record. When I did the initial 
installation with the latest the net install cd I chose the default 
desktop partition scheme, which I believe (if I am not mistaken) was /, 
/usr, and a home partitions. / would have my kernels, root directory and 
grub.

So my question is, how do I proceed? I can use a rescue CD to boot into 
the system and mount /, but how would I reinstall what would normally be 
in /? Do I do a reinstall and skip formatting / home?

Any help at all would be appreciated!