you can most likely replace your MBR with the original contents if you issue the comand below (only if you have not written lilo multiple times)
Code:
lilo -u /dev/hdX
where you replace hdX with the hdd that you installed lilo to, most likely hda, but check and recheck, then check again, if you get it wrong it is likely to give you some trouble.
a quote from the lilo manual,
-u [device-name]
Uninstall lilo by copying the saved boot sector
back. The '-s' and '-C' switches may be used with
this option. The device-name is optional. A time-
stamp is checked.
you wil likely NOT require the -s nor the -C switches, they are for a new "savefile" and a path to new config
-s save-file
When lilo writes a new boot sector, it preserves
the former contents of the sector in a file, named
by default /boot/boot.NNNN, where NNNN is the hex*
adecimal representation of the major and minor
device numbers of the drive/partition. This option
specifies the backup save file in one of three
ways: a save directory (default is '/boot') using
the default filename 'boot.NNNN' in the specified
directory; a pathname template to which '.NNNN' is
appended (default would be '/boot/boot'); or the
full pathname of the file, which must include the
correct '.NNNN' suffix. When used with the -u
option, the full file pathname must be specified.
and
-C config-file
lilo Specify an alternate pathname for the configu*
ration file. This option overrides the use of the
default configuration file, /etc/lilo.conf.