[Discuss] I, uh, deleted the wrong kernel....

[Rich Pieri]

Sounds like you used rm to delete the files. That's bad on anything
using Debian packages. Fix the first is to restore those files from
backup or possibly another system (although you may have problems with
initrds if you do this) and run apt-get -f (I think it's -f) to fix any
outstanding problems. Fix the second is what Peter suggested: back up
your stuff and reinstall from scratch.

Fix the second is probably your best option at this point. It's an
opportunity to size your partitions better and to move /home to a
dedicated partition or device.

Don't install Ubuntu over Ubuntu without reformatting. You will end up
with a broken system if you do.

-- 
Rich P.