Vista - User Profile Error - Logged on with a Temporary Profile

After it happened an obscene number of times. I've disabled User Account Controls and haven't had an issue since. I think the UAC was somehow changed in one of the updates some time in the past few months. It's all an issue with not having administrative rights and temp files from what I'm seeing although the temp files are there. Some type of circular issues?

Hi Brink,
wow, there are other people with this error, gives me hope.
Last night I went to bed, computer was switched on and online. When I looked in he morning, the screen was black, only the mouse arrow was on the screen. I tried to restart it and then all kinds of trouble happened. I was asked to type in the product key, windows would take an awful long time to load, "preparing your desktop" would show up and then, when fully loaded, I would get the news "Your user profile was not loaded correctly! You have been logged on with a temporary profile. Changes you make to this computer will be lost when you log off. Please see the event log for details or contact your administrator."
I tried to press F8 when starting and did the whole recovery thing etc. and I even tried to restore the system, but there is no reference point available prior to the first time I restarted the System after the improper shutdown in the night. How can it happen that a whole profile gets deleted without sitting at the computer or doing anything?
I do not have access to anything that was before the "improper shutdown". I tried to run and antivirus system, it scanned all the data that I cannot access anymore, therefore all my pics and documents seem to be there somewhere. I only had one Administrator Profile on my computer, no roaming etc.
When I tried to start the computer in the regular mode, this temporary profile would still show up.

Does anyone know what happened here? And could anyone tell me what to do to access all my pictures, documents etc. again? (Lucky me, I haven't done a backup)

Thank you very much for your work here, looking forward to a reply soon.