I agree with Barry. 11.04 is a major change from 10.10 and there are many
things to go wrong. The OP was right in thinking he/ she should not have
tried to skip versions. The upgrade path is 10.04 -> 10.10 -> 11.04 or wait
and go 10.04 -> 12.04 (next April). People who want to try 11.04 but are
wary should consider installing a second desktop environment such as KDE or
XFCE so you can fix potential problems from the GUI. I have heard some
people try to install both Unity and GNOME 3 and found neither would work
because they are incompatible. With a second DE you can change to the
alternate at GDM login and fix whatever is not working. People who do not
like Unity can then consider trying the alternative DE because classic GNOME
will disappear in the fall.