System crash during upgrade

[Γιάννης Παπαδόπουλος]

Good morning,
Before removing the previous kernels (see previous mail) I decided to do 
the first upgrade after Kubuntu Flight 5. I downloaded yesterday's daily 
install cd, I typed sudo apt-get dist-upgrade and the process started 
without problem. At some point the upgrade stopped and I was prompted 
that there was an error. I retyped apt-get dist-upgrade but it didn't 
function. I decided to reboot but X-windows had crashed and I received a 
message that I should manually run chkfs if I remember well. Being a 
simple user I copied a command suggested. When I rebooted grub wouldn't 
load and I received an "error 17" message. At this point I decided to 
reinstall flight 5. I solved the problem this way.
I just would like to know what is the appropriate move in a similar 
situation for a complete newbie.
1. Shall I try again to upgrade using the same cd?
2. Shall I download today's current cd?
3. Is there another command I should type?
4. If grub doesn't boot is there a way to fix it without having to 
reinstall Kubuntu?
Thanks again

Yannis