From the Suse Linux help site:
Under Windows XP, you can restore the original MBR (thus uninstalling Lilo) as follows:
Boot from the Windows XP CD, press the key "R" in the setup in order to start the restoration console. Select your Windows XP installation from the list, and enter the administrator password. Enter the command "FIXMBR" at the input prompt and confirm the next question with "y". Finally, use "exit" to restore the computer.