Hmmmm........... Have you ever heard of the two words "back up" ?
I back everything up before upgrading or doing a fresh install. I had no issues with my home desktop machine I did have an issue with my laptop. It upgraded ok......... I had to rebuild a couple of things that would run with the new kernel, everything was fine. Then all of a sudden....... X quit working, and it would not even boot in a low level. The rescue CD didn't do me a bit of good..........
Well.......(since I had things backed up)...... I just did a fresh install.
Everything is happy now. Yes, it is more time consuming, but well worth the effort as I learned...........