Welcome to LQ. There should be no reason to get nervous. Linux isn't that bad
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Since you can only get into Linux, log in, open a terminal session (the thing that looks like a dos box) and do the following:
su root (then type root's password).
fdisk -l (that is a little L, BTW, and post the outcome here)
cat /etc/lilo.conf (and post the outcome here)
exit (returns you to a normal user)
This will give us the information about the partitions on your harddisk (from fdisk) and show us how your lilo is configured. With any luck, you will only need to change the settings in your lilo.conf file, and then re-run lilo.
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Oh, by the way. The lilo.conf file can be quite large, so you might want to do this, instead
cat /etc/lilo.conf > ~/lilooutput and then open this file (which should be in your home directory) with your text editor, and post the contents here.
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