Update problems

[Preston Smith]

Thanks for your help with partitioning.  I decided to go with the default 
partion configuration

There are 120 updated packages available

When I try to get them I receive the following

Could not open cache - Adept Updater
The APT Database could not be opened! This may be caused by incorrect APT 
configuration or some similar problem. Try running apt-setup and apt-get 
update in terminal and see if it helps to resolve the problem.

When I try to do as suggested from the Terminal I receive the following:

preston at Kubuntu:~$ apt-get update
E: Could not open lock file /var/lib/apt/lists/lock - open (13 Permission 
denied                                                              )
E: Unable to lock the list directory
preston at Kubuntu:~$ su
Password:
su: Authentication failure
Sorry.
preston at Kubuntu:~$ sudo
usage: sudo -K | -L | -V | -h | -k | -l | -v
usage: sudo [-HPSb] [-p prompt] [-u username|#uid]
            { -e file [...] | -i | -s | <command> }
preston at Kubuntu:~$ kubuntu
bash: kubuntu: command not found
preston at Kubuntu:~$ apt-setup
bash: apt-setup: command not found
preston at Kubuntu:~$

Help please.  I do not know what to do to fix this

Thanks

Preston