I did the same thing. Screwed up My HDD, and got the lovely green text of death screen. BUT!!! Heres how i got it back together...
Booted a DVD-RW with evox set the IP addy up, FXPd into the drive, renamed my file, corrected the menu.ini and boom baby.. Worked like a champ.
I renamed the ms dashboard to dash-ms.xbe
put the line in the .ini file under section root...
(and dont forget the tdoxxx commands above it.)
Section "Root"
{
Item "MS Dashboard","c:\dash-ms.xbe"
Item "Reboot",@5
Section "System Utils"
{
Item "Network",@6
Item "Harddisk",@7
Item "Flash BIOS",@1
}
}
FXPd evox into the hdd and renamed to xboxdash.xbe
now when it boots i go to evox, and if i want to go to ms dash its right there, and i can put a disc in and reboot and play originals (of course

)
so sweet and short, if you bork your HDD, you can always recover it via RAW commands from FXP and a burned DVD-RW or CD-RW (as long as it boots). Think about it... its almost the same process as puttin in a new one with the exception u need the evobios burned in.