I am sorry that the people at the ubuntu forum did not help you, but maybe you should have turned somewhere else before whiping your harddrive. Problems in Linux are often recoverable, there is a lot of information for it on the web, and a lot of people who are willing to help if you know how to ask questions the right way(tm).
dist-upgrades in ubuntu are usually less of a pain than what you describe, but it also depends a bit on you. When it comes to the unix world, there is one great peace of advice:
RTFM.
Every mayor Linux distro's documentation will tell you to make a full backup before doing an upgrade, as you should do before every mayor operation on your OS. Hell, you should make regular backups anyway! Everybody accidentally deletes some files from time to time.
And you find advice everywhere to put /home
on a different partition from /
- which would have made it easier for you to at least keep your data when whiping the OS.
You probably won't read that information in ubuntu's colorful clicky-gui-upgrade thingy, but Linux is not windows. Don't click on everything you see, think hard about what could happen before you do it.
A good community would have told you to boot from a live-CD, maybe chroot into your system and have a look whats wrong - and if you find out it is non-recoverable, at least rescue your data.
To finally answer your question:
Not a single problem with Jaunty here. Upgraded from Hardy to Intrepid to Jaunty. The box I used before that made Breezy -> Dapper -> Edgy -> Feisty -> Gutsy -> Hardy -> Intrepid without problems that I couldn't handle.