Faulty tree

[Jim Smith]

Just completed the upgrade to 10.04.1 today. Something went wrong at the 
end of the upgrade and now a lot of software just doesn't work or seems 
to be unrecognised by the menu system. Firefox unfortunately is the 
worst case. Synaptic or any other package manager doesn't want to work 
either, when I try to run any pkg manager I get the error message 
"Reading package lists... Done
Segmentation faulty tree... 50%"
I had done all the updates available just prior to the upgrade.
Is there something that can be done?
Any advice will be much appreciated.

Thanks

Jim

-- 
Its only a hobby, only a hobby, only a hobby, only a ho............