Does sound like the install of Xubuntu isn't quite 100% if you are
doing what should work but it doesn't. Not such a huge job doing a
fresh install of Ubuntu so might as well go for it :-)

I like the clean lines of Xubuntu and the lighter strain on an older
system. Have a friend in Bhopal was having lot of trouble with Ubuntu
even after boosting memory and got him to install the Xubuntu desktop
which has been performing well ever since :-)

Prefer Kubuntu for the power user and have really grown to like 12.04
over the months of using it. Sure it has some quirks but all OS's do
so nothing new there <lol>