If you need a rescue disk, go to:
http://www.toms.net/rb/home.html
The site is for a program called Tom's Root Boot. You can, either through DOS or *nix, create a floppy disk with a fully functional *nix.
Once logged in as root, you can mount the devices manually and work from there.
Sounds like I'd make a copy of your latest kernel image right away.
Hope that helps.