[immortality]

i deleted some files due to loss of memory and after restarting an error about loosing a neogrub.mfr was shown.
Since i had burned a super grub 2 disc entered to ubuntu (11.10) and typed some commands that was at a site to correct it.but now windows's(xp64 and 7) didn't loaded so i used recovery in windows cd.
And after that restart.now three boot line are appeared but now i can't enter linux.
One pointer is shown with this message:grub rescue>
And doesn't recognize commands i type.
What should i do?what commands have to put there?