Karmic freezes

I have two computers running Linux, The upgrades from 9.04 to 9.10 went well, All seemed to work and on one it does without problems. The other however freezes regularly. the last time, I clicked "system" --> Administration and then tried to move to Update Manager, the system froze on the Firestarter icon and does not respond to any mouse clicks. Have to restart the system to get out of this. This type of freezing happens in other admin items also.

I, through Synaptic Package Manager, installed "Simple-Backup" I cannot find it on the system, whereas the other system lists it under the "System--> Administration" menu