I'm in a bad position right now

[Vostrocity]

I finally decided to upgrade to 10.10 today. I'm at the Installing Upgrades step and for no apparent reason, my CPU has jumped to 100% (even though System Monitor shows every process as 0%) and my HDD is also spinning nonstop. What the heck is happening? Should I cut the power or wait and hope it finishes before my HDD burns out?

[CharlesA]

Let it sit there for a bit. There is no way it would just "burn out" due to lots of HDD activity and having the CPU peaked.

If you power it off now, it's more then likely you'd break the system.

[Vostrocity]

I waited for 15 min and it barely made any progress so I turned it off. The CPU was running at max the whole time and my laptop was getting hot. My HDD is almost 4 years old and I haven't backed up in a week so I didn't want to take any chances of maxxing out the read write cycles still left on it (I know there's not necessarily a set limit but wear is wear). I booted up again and was happy to see that most things still worked and some things were upgraded. The update manager actually told me I had an incomplete upgrade and asked me to complete it. I chose yes but then it failed to find anything to upgrade so that was that. The system still works but I'm not sure whether or not all the components were upgraded (progress was at 33% when I shut down).

[dino99]

before upgrading, its a good idea to clean the system as much as you can, desactivate all the non genuine repo (ppa), run fsck on reboot, and check for free space of course, and use the main server.

[CharlesA]

Ouch. Give it a shot again after following dino99's advice.