Boot linux single or rescue on bootup (be quick on the draw on the boot up to get the interactive thingy) or by using either your boot floppy made during install or install CD1.
Once you have access to the system, the command passwd
allows you to change your root password and passwd <user>
does the same for the user.
See the Mandrake pages for explicit details on how they boot to linux single and rescue as distros vary in the amount of automation.
Windows XP Recovery Console
# I hosed my box
LILO fails: Error messages and their interpretation
LILO mini HOWTO
Multiboot with LILO HOWTO
LILO, Linux Crash Rescue HOW-TO
Installing a bootloader
When you do things with MicrosoftXP, sometimes it tries to "fix" some Linux partitions.
Rule: Install Windows first and on the first primary
partition of the hard drive, then install Linux.
If you are lucky and Windows tools ignore your Linux partitions and leave them alone, all you will have to do after is to boot to Linux and re-install lilo.