I do not clearly remember all things happenned when I upgraded mine.
But, I also got many error messages that almost frustrating me but not too screwed.
I don't know if this help you but tell you what I went through.
Before upgrading just do some of these,
- Try to uninstall some non essential program.
- Deactivate any antivirus and any firewall programs (comodo have stuck me before, but able to reconfigure it).
- Also see if you have daemon-Tools installed.
Just try to upgrade in a bit clean system environment.
Hope you will soon see the simpler and nicer Win 7 than your Vista.