Download and burn the Puppy LuPu 525 Live CD, upon starting it should find your
Ubuntu installation and offer to repair if it sees an "unclean hard drive"
shutdown situation. Did you try to run Ubuntu 10.10 from Live CD to select
repair of Ubuntu? From Ubuntu Live CD, go to System>Administration>Disk
Utility...you'll see Smart and Check file system...Report back if you need more
help.
Don't worry for the Windows' side, since your Windows' Install CD can repair it
to start over with a clean Ubuntu install. Puppy or Ubuntu Live CDs can mount
and copy files from the hard drive to an external USB mounted hard drive, too.