Hi,
I wrote a little step-by-step guide with screenshots to illustrate the upgrade process from Ubuntu 12.10 Quantal Quetzal to 13.04 Raring Ringtail very precisely.
I hope this screenshot-guide is of use for those looking to upgrade to the latest (and IMHO greatest) version of Ubuntu
http://www.maknesium.de/upgrade-to-u...thout-problems
I am looking forward to your feedback!
Maknesium