One more idea...

Debian still has a floppy based netboot. You need 5 floppies to get up
and running, and then it's all network based. You could try changing
the installers sources.list to Ubuntu's sources...no idea if that will
work. Or you could get enough of Debain installed and follow the
Installation from another Disto instructions,
https://help.ubuntu.com/community/Installation/FromAnotherDistro?highlight=%28install%29,
or easiest of all just stick with Debian. :)

Assuming you can boot the laptop from floppy, going with Debain
instead of Ubuntu might be your best bet. :)

-- 
Andrew S. Zbikowski | http://andy.zibnet.us
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